diff options
Diffstat (limited to 'users/grfn/achilles/src')
27 files changed, 4769 insertions, 0 deletions
diff --git a/users/grfn/achilles/src/ast/hir.rs b/users/grfn/achilles/src/ast/hir.rs new file mode 100644 index 000000000000..cdfaef567d7a --- /dev/null +++ b/users/grfn/achilles/src/ast/hir.rs @@ -0,0 +1,364 @@ +use std::collections::HashMap; + +use itertools::Itertools; + +use super::{BinaryOperator, Ident, Literal, UnaryOperator}; + +#[derive(Debug, PartialEq, Eq, Clone)] +pub enum Pattern<'a, T> { + Id(Ident<'a>, T), + Tuple(Vec<Pattern<'a, T>>), +} + +impl<'a, T> Pattern<'a, T> { + pub fn to_owned(&self) -> Pattern<'static, T> + where + T: Clone, + { + match self { + Pattern::Id(id, t) => Pattern::Id(id.to_owned(), t.clone()), + Pattern::Tuple(pats) => { + Pattern::Tuple(pats.into_iter().map(Pattern::to_owned).collect()) + } + } + } + + pub fn traverse_type<F, U, E>(self, f: F) -> Result<Pattern<'a, U>, E> + where + F: Fn(T) -> Result<U, E> + Clone, + { + match self { + Pattern::Id(id, t) => Ok(Pattern::Id(id, f(t)?)), + Pattern::Tuple(pats) => Ok(Pattern::Tuple( + pats.into_iter() + .map(|pat| pat.traverse_type(f.clone())) + .collect::<Result<Vec<_>, _>>()?, + )), + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub struct Binding<'a, T> { + pub pat: Pattern<'a, T>, + pub body: Expr<'a, T>, +} + +impl<'a, T> Binding<'a, T> { + fn to_owned(&self) -> Binding<'static, T> + where + T: Clone, + { + Binding { + pat: self.pat.to_owned(), + body: self.body.to_owned(), + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub enum Expr<'a, T> { + Ident(Ident<'a>, T), + + Literal(Literal<'a>, T), + + Tuple(Vec<Expr<'a, T>>, T), + + UnaryOp { + op: UnaryOperator, + rhs: Box<Expr<'a, T>>, + type_: T, + }, + + BinaryOp { + lhs: Box<Expr<'a, T>>, + op: BinaryOperator, + rhs: Box<Expr<'a, T>>, + type_: T, + }, + + Let { + bindings: Vec<Binding<'a, T>>, + body: Box<Expr<'a, T>>, + type_: T, + }, + + If { + condition: Box<Expr<'a, T>>, + then: Box<Expr<'a, T>>, + else_: Box<Expr<'a, T>>, + type_: T, + }, + + Fun { + type_args: Vec<Ident<'a>>, + args: Vec<(Ident<'a>, T)>, + body: Box<Expr<'a, T>>, + type_: T, + }, + + Call { + fun: Box<Expr<'a, T>>, + type_args: HashMap<Ident<'a>, T>, + args: Vec<Expr<'a, T>>, + type_: T, + }, +} + +impl<'a, T> Expr<'a, T> { + pub fn type_(&self) -> &T { + match self { + Expr::Ident(_, t) => t, + Expr::Literal(_, t) => t, + Expr::Tuple(_, t) => t, + Expr::UnaryOp { type_, .. } => type_, + Expr::BinaryOp { type_, .. } => type_, + Expr::Let { type_, .. } => type_, + Expr::If { type_, .. } => type_, + Expr::Fun { type_, .. } => type_, + Expr::Call { type_, .. } => type_, + } + } + + pub fn traverse_type<F, U, E>(self, f: F) -> Result<Expr<'a, U>, E> + where + F: Fn(T) -> Result<U, E> + Clone, + { + match self { + Expr::Ident(id, t) => Ok(Expr::Ident(id, f(t)?)), + Expr::Literal(lit, t) => Ok(Expr::Literal(lit, f(t)?)), + Expr::UnaryOp { op, rhs, type_ } => Ok(Expr::UnaryOp { + op, + rhs: Box::new(rhs.traverse_type(f.clone())?), + type_: f(type_)?, + }), + Expr::BinaryOp { + lhs, + op, + rhs, + type_, + } => Ok(Expr::BinaryOp { + lhs: Box::new(lhs.traverse_type(f.clone())?), + op, + rhs: Box::new(rhs.traverse_type(f.clone())?), + type_: f(type_)?, + }), + Expr::Let { + bindings, + body, + type_, + } => Ok(Expr::Let { + bindings: bindings + .into_iter() + .map(|Binding { pat, body }| { + Ok(Binding { + pat: pat.traverse_type(f.clone())?, + body: body.traverse_type(f.clone())?, + }) + }) + .collect::<Result<Vec<_>, E>>()?, + body: Box::new(body.traverse_type(f.clone())?), + type_: f(type_)?, + }), + Expr::If { + condition, + then, + else_, + type_, + } => Ok(Expr::If { + condition: Box::new(condition.traverse_type(f.clone())?), + then: Box::new(then.traverse_type(f.clone())?), + else_: Box::new(else_.traverse_type(f.clone())?), + type_: f(type_)?, + }), + Expr::Fun { + args, + type_args, + body, + type_, + } => Ok(Expr::Fun { + args: args + .into_iter() + .map(|(id, t)| Ok((id, f.clone()(t)?))) + .collect::<Result<Vec<_>, E>>()?, + type_args, + body: Box::new(body.traverse_type(f.clone())?), + type_: f(type_)?, + }), + Expr::Call { + fun, + type_args, + args, + type_, + } => Ok(Expr::Call { + fun: Box::new(fun.traverse_type(f.clone())?), + type_args: type_args + .into_iter() + .map(|(id, ty)| Ok((id, f.clone()(ty)?))) + .collect::<Result<HashMap<_, _>, E>>()?, + args: args + .into_iter() + .map(|e| e.traverse_type(f.clone())) + .collect::<Result<Vec<_>, E>>()?, + type_: f(type_)?, + }), + Expr::Tuple(members, t) => Ok(Expr::Tuple( + members + .into_iter() + .map(|t| t.traverse_type(f.clone())) + .try_collect()?, + f(t)?, + )), + } + } + + pub fn to_owned(&self) -> Expr<'static, T> + where + T: Clone, + { + match self { + Expr::Ident(id, t) => Expr::Ident(id.to_owned(), t.clone()), + Expr::Literal(lit, t) => Expr::Literal(lit.to_owned(), t.clone()), + Expr::UnaryOp { op, rhs, type_ } => Expr::UnaryOp { + op: *op, + rhs: Box::new((**rhs).to_owned()), + type_: type_.clone(), + }, + Expr::BinaryOp { + lhs, + op, + rhs, + type_, + } => Expr::BinaryOp { + lhs: Box::new((**lhs).to_owned()), + op: *op, + rhs: Box::new((**rhs).to_owned()), + type_: type_.clone(), + }, + Expr::Let { + bindings, + body, + type_, + } => Expr::Let { + bindings: bindings.iter().map(|b| b.to_owned()).collect(), + body: Box::new((**body).to_owned()), + type_: type_.clone(), + }, + Expr::If { + condition, + then, + else_, + type_, + } => Expr::If { + condition: Box::new((**condition).to_owned()), + then: Box::new((**then).to_owned()), + else_: Box::new((**else_).to_owned()), + type_: type_.clone(), + }, + Expr::Fun { + args, + type_args, + body, + type_, + } => Expr::Fun { + args: args + .iter() + .map(|(id, t)| (id.to_owned(), t.clone())) + .collect(), + type_args: type_args.iter().map(|arg| arg.to_owned()).collect(), + body: Box::new((**body).to_owned()), + type_: type_.clone(), + }, + Expr::Call { + fun, + type_args, + args, + type_, + } => Expr::Call { + fun: Box::new((**fun).to_owned()), + type_args: type_args + .iter() + .map(|(id, t)| (id.to_owned(), t.clone())) + .collect(), + args: args.iter().map(|e| e.to_owned()).collect(), + type_: type_.clone(), + }, + Expr::Tuple(members, t) => { + Expr::Tuple(members.into_iter().map(Expr::to_owned).collect(), t.clone()) + } + } + } +} + +#[derive(Debug, Clone, PartialEq, Eq)] +pub enum Decl<'a, T> { + Fun { + name: Ident<'a>, + type_args: Vec<Ident<'a>>, + args: Vec<(Ident<'a>, T)>, + body: Box<Expr<'a, T>>, + type_: T, + }, + + Extern { + name: Ident<'a>, + arg_types: Vec<T>, + ret_type: T, + }, +} + +impl<'a, T> Decl<'a, T> { + pub fn name(&self) -> &Ident<'a> { + match self { + Decl::Fun { name, .. } => name, + Decl::Extern { name, .. } => name, + } + } + + pub fn set_name(&mut self, new_name: Ident<'a>) { + match self { + Decl::Fun { name, .. } => *name = new_name, + Decl::Extern { name, .. } => *name = new_name, + } + } + + pub fn type_(&self) -> Option<&T> { + match self { + Decl::Fun { type_, .. } => Some(type_), + Decl::Extern { .. } => None, + } + } + + pub fn traverse_type<F, U, E>(self, f: F) -> Result<Decl<'a, U>, E> + where + F: Fn(T) -> Result<U, E> + Clone, + { + match self { + Decl::Fun { + name, + type_args, + args, + body, + type_, + } => Ok(Decl::Fun { + name, + type_args, + args: args + .into_iter() + .map(|(id, t)| Ok((id, f(t)?))) + .try_collect()?, + body: Box::new(body.traverse_type(f.clone())?), + type_: f(type_)?, + }), + Decl::Extern { + name, + arg_types, + ret_type, + } => Ok(Decl::Extern { + name, + arg_types: arg_types.into_iter().map(f.clone()).try_collect()?, + ret_type: f(ret_type)?, + }), + } + } +} diff --git a/users/grfn/achilles/src/ast/mod.rs b/users/grfn/achilles/src/ast/mod.rs new file mode 100644 index 000000000000..5438d29d2cf7 --- /dev/null +++ b/users/grfn/achilles/src/ast/mod.rs @@ -0,0 +1,484 @@ +pub(crate) mod hir; + +use std::borrow::Cow; +use std::collections::HashMap; +use std::convert::TryFrom; +use std::fmt::{self, Display, Formatter}; + +use itertools::Itertools; + +#[derive(Debug, PartialEq, Eq)] +pub struct InvalidIdentifier<'a>(Cow<'a, str>); + +#[derive(Debug, PartialEq, Eq, Hash, Clone)] +pub struct Ident<'a>(pub Cow<'a, str>); + +impl<'a> From<&'a Ident<'a>> for &'a str { + fn from(id: &'a Ident<'a>) -> Self { + id.0.as_ref() + } +} + +impl<'a> Display for Ident<'a> { + fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result { + write!(f, "{}", self.0) + } +} + +impl<'a> Ident<'a> { + pub fn to_owned(&self) -> Ident<'static> { + Ident(Cow::Owned(self.0.clone().into_owned())) + } + + /// Construct an identifier from a &str without checking that it's a valid identifier + pub fn from_str_unchecked(s: &'a str) -> Self { + debug_assert!(is_valid_identifier(s)); + Self(Cow::Borrowed(s)) + } + + pub fn from_string_unchecked(s: String) -> Self { + debug_assert!(is_valid_identifier(&s)); + Self(Cow::Owned(s)) + } +} + +pub fn is_valid_identifier<S>(s: &S) -> bool +where + S: AsRef<str> + ?Sized, +{ + s.as_ref() + .chars() + .any(|c| !c.is_alphanumeric() || !"_".contains(c)) +} + +impl<'a> TryFrom<&'a str> for Ident<'a> { + type Error = InvalidIdentifier<'a>; + + fn try_from(s: &'a str) -> Result<Self, Self::Error> { + if is_valid_identifier(s) { + Ok(Ident(Cow::Borrowed(s))) + } else { + Err(InvalidIdentifier(Cow::Borrowed(s))) + } + } +} + +impl<'a> TryFrom<String> for Ident<'a> { + type Error = InvalidIdentifier<'static>; + + fn try_from(s: String) -> Result<Self, Self::Error> { + if is_valid_identifier(&s) { + Ok(Ident(Cow::Owned(s))) + } else { + Err(InvalidIdentifier(Cow::Owned(s))) + } + } +} + +#[derive(Debug, PartialEq, Eq, Copy, Clone)] +pub enum BinaryOperator { + /// `+` + Add, + + /// `-` + Sub, + + /// `*` + Mul, + + /// `/` + Div, + + /// `^` + Pow, + + /// `==` + Equ, + + /// `!=` + Neq, +} + +#[derive(Debug, PartialEq, Eq, Copy, Clone)] +pub enum UnaryOperator { + /// ! + Not, + + /// - + Neg, +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub enum Literal<'a> { + Unit, + Int(u64), + Bool(bool), + String(Cow<'a, str>), +} + +impl<'a> Literal<'a> { + pub fn to_owned(&self) -> Literal<'static> { + match self { + Literal::Int(i) => Literal::Int(*i), + Literal::Bool(b) => Literal::Bool(*b), + Literal::String(s) => Literal::String(Cow::Owned(s.clone().into_owned())), + Literal::Unit => Literal::Unit, + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub enum Pattern<'a> { + Id(Ident<'a>), + Tuple(Vec<Pattern<'a>>), +} + +impl<'a> Pattern<'a> { + pub fn to_owned(&self) -> Pattern<'static> { + match self { + Pattern::Id(id) => Pattern::Id(id.to_owned()), + Pattern::Tuple(pats) => Pattern::Tuple(pats.iter().map(Pattern::to_owned).collect()), + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub struct Binding<'a> { + pub pat: Pattern<'a>, + pub type_: Option<Type<'a>>, + pub body: Expr<'a>, +} + +impl<'a> Binding<'a> { + fn to_owned(&self) -> Binding<'static> { + Binding { + pat: self.pat.to_owned(), + type_: self.type_.as_ref().map(|t| t.to_owned()), + body: self.body.to_owned(), + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub enum Expr<'a> { + Ident(Ident<'a>), + + Literal(Literal<'a>), + + UnaryOp { + op: UnaryOperator, + rhs: Box<Expr<'a>>, + }, + + BinaryOp { + lhs: Box<Expr<'a>>, + op: BinaryOperator, + rhs: Box<Expr<'a>>, + }, + + Let { + bindings: Vec<Binding<'a>>, + body: Box<Expr<'a>>, + }, + + If { + condition: Box<Expr<'a>>, + then: Box<Expr<'a>>, + else_: Box<Expr<'a>>, + }, + + Fun(Box<Fun<'a>>), + + Call { + fun: Box<Expr<'a>>, + args: Vec<Expr<'a>>, + }, + + Tuple(Vec<Expr<'a>>), + + Ascription { + expr: Box<Expr<'a>>, + type_: Type<'a>, + }, +} + +impl<'a> Expr<'a> { + pub fn to_owned(&self) -> Expr<'static> { + match self { + Expr::Ident(ref id) => Expr::Ident(id.to_owned()), + Expr::Literal(ref lit) => Expr::Literal(lit.to_owned()), + Expr::Tuple(ref members) => { + Expr::Tuple(members.into_iter().map(Expr::to_owned).collect()) + } + Expr::UnaryOp { op, rhs } => Expr::UnaryOp { + op: *op, + rhs: Box::new((**rhs).to_owned()), + }, + Expr::BinaryOp { lhs, op, rhs } => Expr::BinaryOp { + lhs: Box::new((**lhs).to_owned()), + op: *op, + rhs: Box::new((**rhs).to_owned()), + }, + Expr::Let { bindings, body } => Expr::Let { + bindings: bindings.iter().map(|binding| binding.to_owned()).collect(), + body: Box::new((**body).to_owned()), + }, + Expr::If { + condition, + then, + else_, + } => Expr::If { + condition: Box::new((**condition).to_owned()), + then: Box::new((**then).to_owned()), + else_: Box::new((**else_).to_owned()), + }, + Expr::Fun(fun) => Expr::Fun(Box::new((**fun).to_owned())), + Expr::Call { fun, args } => Expr::Call { + fun: Box::new((**fun).to_owned()), + args: args.iter().map(|arg| arg.to_owned()).collect(), + }, + Expr::Ascription { expr, type_ } => Expr::Ascription { + expr: Box::new((**expr).to_owned()), + type_: type_.to_owned(), + }, + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub struct Arg<'a> { + pub ident: Ident<'a>, + pub type_: Option<Type<'a>>, +} + +impl<'a> Arg<'a> { + pub fn to_owned(&self) -> Arg<'static> { + Arg { + ident: self.ident.to_owned(), + type_: self.type_.as_ref().map(Type::to_owned), + } + } +} + +impl<'a> TryFrom<&'a str> for Arg<'a> { + type Error = <Ident<'a> as TryFrom<&'a str>>::Error; + + fn try_from(value: &'a str) -> Result<Self, Self::Error> { + Ok(Arg { + ident: Ident::try_from(value)?, + type_: None, + }) + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub struct Fun<'a> { + pub args: Vec<Arg<'a>>, + pub body: Expr<'a>, +} + +impl<'a> Fun<'a> { + pub fn to_owned(&self) -> Fun<'static> { + Fun { + args: self.args.iter().map(|arg| arg.to_owned()).collect(), + body: self.body.to_owned(), + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub enum Decl<'a> { + Fun { + name: Ident<'a>, + body: Fun<'a>, + }, + Ascription { + name: Ident<'a>, + type_: Type<'a>, + }, + Extern { + name: Ident<'a>, + type_: FunctionType<'a>, + }, +} + +//// + +#[derive(Debug, PartialEq, Eq, Clone)] +pub struct FunctionType<'a> { + pub args: Vec<Type<'a>>, + pub ret: Box<Type<'a>>, +} + +impl<'a> FunctionType<'a> { + pub fn to_owned(&self) -> FunctionType<'static> { + FunctionType { + args: self.args.iter().map(|a| a.to_owned()).collect(), + ret: Box::new((*self.ret).to_owned()), + } + } +} + +impl<'a> Display for FunctionType<'a> { + fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result { + write!(f, "fn {} -> {}", self.args.iter().join(", "), self.ret) + } +} + +#[derive(Debug, PartialEq, Eq, Clone)] +pub enum Type<'a> { + Int, + Float, + Bool, + CString, + Unit, + Tuple(Vec<Type<'a>>), + Var(Ident<'a>), + Function(FunctionType<'a>), +} + +impl<'a> Type<'a> { + pub fn to_owned(&self) -> Type<'static> { + match self { + Type::Int => Type::Int, + Type::Float => Type::Float, + Type::Bool => Type::Bool, + Type::CString => Type::CString, + Type::Unit => Type::Unit, + Type::Var(v) => Type::Var(v.to_owned()), + Type::Function(f) => Type::Function(f.to_owned()), + Type::Tuple(members) => Type::Tuple(members.iter().map(Type::to_owned).collect()), + } + } + + pub fn alpha_equiv(&self, other: &Self) -> bool { + fn do_alpha_equiv<'a>( + substs: &mut HashMap<&'a Ident<'a>, &'a Ident<'a>>, + lhs: &'a Type, + rhs: &'a Type, + ) -> bool { + match (lhs, rhs) { + (Type::Var(v1), Type::Var(v2)) => substs.entry(v1).or_insert(v2) == &v2, + ( + Type::Function(FunctionType { + args: args1, + ret: ret1, + }), + Type::Function(FunctionType { + args: args2, + ret: ret2, + }), + ) => { + args1.len() == args2.len() + && args1 + .iter() + .zip(args2) + .all(|(a1, a2)| do_alpha_equiv(substs, a1, a2)) + && do_alpha_equiv(substs, ret1, ret2) + } + _ => lhs == rhs, + } + } + + let mut substs = HashMap::new(); + do_alpha_equiv(&mut substs, self, other) + } + + pub fn traverse_type_vars<'b, F>(self, mut f: F) -> Type<'b> + where + F: FnMut(Ident<'a>) -> Type<'b> + Clone, + { + match self { + Type::Var(tv) => f(tv), + Type::Function(FunctionType { args, ret }) => Type::Function(FunctionType { + args: args + .into_iter() + .map(|t| t.traverse_type_vars(f.clone())) + .collect(), + ret: Box::new(ret.traverse_type_vars(f)), + }), + Type::Int => Type::Int, + Type::Float => Type::Float, + Type::Bool => Type::Bool, + Type::CString => Type::CString, + Type::Tuple(members) => Type::Tuple( + members + .into_iter() + .map(|t| t.traverse_type_vars(f.clone())) + .collect(), + ), + Type::Unit => Type::Unit, + } + } + + pub fn as_tuple(&self) -> Option<&Vec<Type<'a>>> { + if let Self::Tuple(v) = self { + Some(v) + } else { + None + } + } +} + +impl<'a> Display for Type<'a> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + Type::Int => f.write_str("int"), + Type::Float => f.write_str("float"), + Type::Bool => f.write_str("bool"), + Type::CString => f.write_str("cstring"), + Type::Unit => f.write_str("()"), + Type::Var(v) => v.fmt(f), + Type::Function(ft) => ft.fmt(f), + Type::Tuple(ms) => write!(f, "({})", ms.iter().join(", ")), + } + } +} + +#[cfg(test)] +mod tests { + use super::*; + + fn type_var(n: &str) -> Type<'static> { + Type::Var(Ident::try_from(n.to_owned()).unwrap()) + } + + mod alpha_equiv { + use super::*; + + #[test] + fn trivial() { + assert!(Type::Int.alpha_equiv(&Type::Int)); + assert!(!Type::Int.alpha_equiv(&Type::Bool)); + } + + #[test] + fn simple_type_var() { + assert!(type_var("a").alpha_equiv(&type_var("b"))); + } + + #[test] + fn function_with_type_vars_equiv() { + assert!(Type::Function(FunctionType { + args: vec![type_var("a")], + ret: Box::new(type_var("b")), + }) + .alpha_equiv(&Type::Function(FunctionType { + args: vec![type_var("b")], + ret: Box::new(type_var("a")), + }))) + } + + #[test] + fn function_with_type_vars_non_equiv() { + assert!(!Type::Function(FunctionType { + args: vec![type_var("a")], + ret: Box::new(type_var("a")), + }) + .alpha_equiv(&Type::Function(FunctionType { + args: vec![type_var("b")], + ret: Box::new(type_var("a")), + }))) + } + } +} diff --git a/users/grfn/achilles/src/codegen/llvm.rs b/users/grfn/achilles/src/codegen/llvm.rs new file mode 100644 index 000000000000..9a71ac954e00 --- /dev/null +++ b/users/grfn/achilles/src/codegen/llvm.rs @@ -0,0 +1,486 @@ +use std::convert::{TryFrom, TryInto}; +use std::path::Path; +use std::result; + +use inkwell::basic_block::BasicBlock; +use inkwell::builder::Builder; +pub use inkwell::context::Context; +use inkwell::module::Module; +use inkwell::support::LLVMString; +use inkwell::types::{BasicType, BasicTypeEnum, FunctionType, IntType, StructType}; +use inkwell::values::{AnyValueEnum, BasicValueEnum, FunctionValue, StructValue}; +use inkwell::{AddressSpace, IntPredicate}; +use itertools::Itertools; +use thiserror::Error; + +use crate::ast::hir::{Binding, Decl, Expr, Pattern}; +use crate::ast::{BinaryOperator, Ident, Literal, Type, UnaryOperator}; +use crate::common::env::Env; + +#[derive(Debug, PartialEq, Eq, Error)] +pub enum Error { + #[error("Undefined variable {0}")] + UndefinedVariable(Ident<'static>), + + #[error("LLVM Error: {0}")] + LLVMError(String), +} + +impl From<LLVMString> for Error { + fn from(s: LLVMString) -> Self { + Self::LLVMError(s.to_string()) + } +} + +pub type Result<T> = result::Result<T, Error>; + +pub struct Codegen<'ctx, 'ast> { + context: &'ctx Context, + pub module: Module<'ctx>, + builder: Builder<'ctx>, + env: Env<&'ast Ident<'ast>, AnyValueEnum<'ctx>>, + function_stack: Vec<FunctionValue<'ctx>>, + identifier_counter: u32, +} + +impl<'ctx, 'ast> Codegen<'ctx, 'ast> { + pub fn new(context: &'ctx Context, module_name: &str) -> Self { + let module = context.create_module(module_name); + let builder = context.create_builder(); + Self { + context, + module, + builder, + env: Default::default(), + function_stack: Default::default(), + identifier_counter: 0, + } + } + + pub fn new_function<'a>( + &'a mut self, + name: &str, + ty: FunctionType<'ctx>, + ) -> &'a FunctionValue<'ctx> { + self.function_stack + .push(self.module.add_function(name, ty, None)); + let basic_block = self.append_basic_block("entry"); + self.builder.position_at_end(basic_block); + self.function_stack.last().unwrap() + } + + pub fn finish_function(&mut self, res: Option<&BasicValueEnum<'ctx>>) -> FunctionValue<'ctx> { + self.builder.build_return(match res { + // lol + Some(val) => Some(val), + None => None, + }); + self.function_stack.pop().unwrap() + } + + pub fn append_basic_block(&self, name: &str) -> BasicBlock<'ctx> { + self.context + .append_basic_block(*self.function_stack.last().unwrap(), name) + } + + fn bind_pattern(&mut self, pat: &'ast Pattern<'ast, Type>, val: AnyValueEnum<'ctx>) { + match pat { + Pattern::Id(id, _) => self.env.set(id, val), + Pattern::Tuple(pats) => { + for (i, pat) in pats.iter().enumerate() { + let member = self + .builder + .build_extract_value( + StructValue::try_from(val).unwrap(), + i as _, + "pat_bind", + ) + .unwrap(); + self.bind_pattern(pat, member.into()); + } + } + } + } + + pub fn codegen_expr( + &mut self, + expr: &'ast Expr<'ast, Type>, + ) -> Result<Option<AnyValueEnum<'ctx>>> { + match expr { + Expr::Ident(id, _) => self + .env + .resolve(id) + .cloned() + .ok_or_else(|| Error::UndefinedVariable(id.to_owned())) + .map(Some), + Expr::Literal(lit, ty) => { + let ty = self.codegen_int_type(ty); + match lit { + Literal::Int(i) => Ok(Some(AnyValueEnum::IntValue(ty.const_int(*i, false)))), + Literal::Bool(b) => Ok(Some(AnyValueEnum::IntValue( + ty.const_int(if *b { 1 } else { 0 }, false), + ))), + Literal::String(s) => Ok(Some( + self.builder + .build_global_string_ptr(s, "s") + .as_pointer_value() + .into(), + )), + Literal::Unit => Ok(None), + } + } + Expr::UnaryOp { op, rhs, .. } => { + let rhs = self.codegen_expr(rhs)?.unwrap(); + match op { + UnaryOperator::Not => unimplemented!(), + UnaryOperator::Neg => Ok(Some(AnyValueEnum::IntValue( + self.builder.build_int_neg(rhs.into_int_value(), "neg"), + ))), + } + } + Expr::BinaryOp { lhs, op, rhs, .. } => { + let lhs = self.codegen_expr(lhs)?.unwrap(); + let rhs = self.codegen_expr(rhs)?.unwrap(); + match op { + BinaryOperator::Add => { + Ok(Some(AnyValueEnum::IntValue(self.builder.build_int_add( + lhs.into_int_value(), + rhs.into_int_value(), + "add", + )))) + } + BinaryOperator::Sub => { + Ok(Some(AnyValueEnum::IntValue(self.builder.build_int_sub( + lhs.into_int_value(), + rhs.into_int_value(), + "add", + )))) + } + BinaryOperator::Mul => { + Ok(Some(AnyValueEnum::IntValue(self.builder.build_int_sub( + lhs.into_int_value(), + rhs.into_int_value(), + "add", + )))) + } + BinaryOperator::Div => Ok(Some(AnyValueEnum::IntValue( + self.builder.build_int_signed_div( + lhs.into_int_value(), + rhs.into_int_value(), + "add", + ), + ))), + BinaryOperator::Pow => unimplemented!(), + BinaryOperator::Equ => Ok(Some(AnyValueEnum::IntValue( + self.builder.build_int_compare( + IntPredicate::EQ, + lhs.into_int_value(), + rhs.into_int_value(), + "eq", + ), + ))), + BinaryOperator::Neq => todo!(), + } + } + Expr::Let { bindings, body, .. } => { + self.env.push(); + for Binding { pat, body, .. } in bindings { + if let Some(val) = self.codegen_expr(body)? { + self.bind_pattern(pat, val); + } + } + let res = self.codegen_expr(body); + self.env.pop(); + res + } + Expr::If { + condition, + then, + else_, + type_, + } => { + let then_block = self.append_basic_block("then"); + let else_block = self.append_basic_block("else"); + let join_block = self.append_basic_block("join"); + let condition = self.codegen_expr(condition)?.unwrap(); + self.builder.build_conditional_branch( + condition.into_int_value(), + then_block, + else_block, + ); + self.builder.position_at_end(then_block); + let then_res = self.codegen_expr(then)?; + self.builder.build_unconditional_branch(join_block); + + self.builder.position_at_end(else_block); + let else_res = self.codegen_expr(else_)?; + self.builder.build_unconditional_branch(join_block); + + self.builder.position_at_end(join_block); + if let Some(phi_type) = self.codegen_type(type_) { + let phi = self.builder.build_phi(phi_type, "join"); + phi.add_incoming(&[ + ( + &BasicValueEnum::try_from(then_res.unwrap()).unwrap(), + then_block, + ), + ( + &BasicValueEnum::try_from(else_res.unwrap()).unwrap(), + else_block, + ), + ]); + Ok(Some(phi.as_basic_value().into())) + } else { + Ok(None) + } + } + Expr::Call { fun, args, .. } => { + if let Expr::Ident(id, _) = &**fun { + let function = self + .module + .get_function(id.into()) + .or_else(|| self.env.resolve(id)?.clone().try_into().ok()) + .ok_or_else(|| Error::UndefinedVariable(id.to_owned()))?; + let args = args + .iter() + .map(|arg| Ok(self.codegen_expr(arg)?.unwrap().try_into().unwrap())) + .collect::<Result<Vec<_>>>()?; + Ok(self + .builder + .build_call(function, &args, "call") + .try_as_basic_value() + .left() + .map(|val| val.into())) + } else { + todo!() + } + } + Expr::Fun { args, body, .. } => { + let fname = self.fresh_ident("f"); + let cur_block = self.builder.get_insert_block().unwrap(); + let env = self.env.save(); // TODO: closures + let function = self.codegen_function(&fname, args, body)?; + self.builder.position_at_end(cur_block); + self.env.restore(env); + Ok(Some(function.into())) + } + Expr::Tuple(members, ty) => { + let values = members + .into_iter() + .map(|expr| self.codegen_expr(expr)) + .collect::<Result<Vec<_>>>()? + .into_iter() + .filter_map(|x| x) + .map(|x| x.try_into().unwrap()) + .collect_vec(); + let field_types = ty.as_tuple().unwrap(); + let tuple_type = self.codegen_tuple_type(field_types); + Ok(Some(tuple_type.const_named_struct(&values).into())) + } + } + } + + pub fn codegen_function( + &mut self, + name: &str, + args: &'ast [(Ident<'ast>, Type)], + body: &'ast Expr<'ast, Type>, + ) -> Result<FunctionValue<'ctx>> { + let arg_types = args + .iter() + .filter_map(|(_, at)| self.codegen_type(at)) + .collect::<Vec<_>>(); + + self.new_function( + name, + match self.codegen_type(body.type_()) { + Some(ret_ty) => ret_ty.fn_type(&arg_types, false), + None => self.context.void_type().fn_type(&arg_types, false), + }, + ); + self.env.push(); + for (i, (arg, _)) in args.iter().enumerate() { + self.env.set( + arg, + self.cur_function().get_nth_param(i as u32).unwrap().into(), + ); + } + let res = self.codegen_expr(body)?; + self.env.pop(); + Ok(self.finish_function(res.map(|av| av.try_into().unwrap()).as_ref())) + } + + pub fn codegen_extern( + &mut self, + name: &str, + args: &'ast [Type], + ret: &'ast Type, + ) -> Result<()> { + let arg_types = args + .iter() + .map(|t| self.codegen_type(t).unwrap()) + .collect::<Vec<_>>(); + self.module.add_function( + name, + match self.codegen_type(ret) { + Some(ret_ty) => ret_ty.fn_type(&arg_types, false), + None => self.context.void_type().fn_type(&arg_types, false), + }, + None, + ); + Ok(()) + } + + pub fn codegen_decl(&mut self, decl: &'ast Decl<'ast, Type>) -> Result<()> { + match decl { + Decl::Fun { + name, args, body, .. + } => { + self.codegen_function(name.into(), args, body)?; + Ok(()) + } + Decl::Extern { + name, + arg_types, + ret_type, + } => self.codegen_extern(name.into(), arg_types, ret_type), + } + } + + pub fn codegen_main(&mut self, expr: &'ast Expr<'ast, Type>) -> Result<()> { + self.new_function("main", self.context.i64_type().fn_type(&[], false)); + let res = self.codegen_expr(expr)?; + if *expr.type_() != Type::Int { + self.builder + .build_return(Some(&self.context.i64_type().const_int(0, false))); + } else { + self.finish_function(res.map(|r| r.try_into().unwrap()).as_ref()); + } + Ok(()) + } + + fn codegen_type(&self, type_: &'ast Type) -> Option<BasicTypeEnum<'ctx>> { + // TODO + match type_ { + Type::Int => Some(self.context.i64_type().into()), + Type::Float => Some(self.context.f64_type().into()), + Type::Bool => Some(self.context.bool_type().into()), + Type::CString => Some( + self.context + .i8_type() + .ptr_type(AddressSpace::Generic) + .into(), + ), + Type::Function(_) => todo!(), + Type::Var(_) => unreachable!(), + Type::Unit => None, + Type::Tuple(ts) => Some(self.codegen_tuple_type(ts).into()), + } + } + + fn codegen_tuple_type(&self, ts: &'ast [Type]) -> StructType<'ctx> { + self.context.struct_type( + ts.iter() + .filter_map(|t| self.codegen_type(t)) + .collect_vec() + .as_slice(), + false, + ) + } + + fn codegen_int_type(&self, type_: &'ast Type) -> IntType<'ctx> { + // TODO + self.context.i64_type() + } + + pub fn print_to_file<P>(&self, path: P) -> Result<()> + where + P: AsRef<Path>, + { + Ok(self.module.print_to_file(path)?) + } + + pub fn binary_to_file<P>(&self, path: P) -> Result<()> + where + P: AsRef<Path>, + { + if self.module.write_bitcode_to_path(path.as_ref()) { + Ok(()) + } else { + Err(Error::LLVMError( + "Error writing bitcode to output path".to_owned(), + )) + } + } + + fn fresh_ident(&mut self, prefix: &str) -> String { + self.identifier_counter += 1; + format!("{}{}", prefix, self.identifier_counter) + } + + fn cur_function(&self) -> &FunctionValue<'ctx> { + self.function_stack.last().unwrap() + } +} + +#[cfg(test)] +mod tests { + use inkwell::execution_engine::JitFunction; + use inkwell::OptimizationLevel; + + use super::*; + + fn jit_eval<T>(expr: &str) -> anyhow::Result<T> { + let expr = crate::parser::expr(expr).unwrap().1; + + let expr = crate::tc::typecheck_expr(expr).unwrap(); + + let context = Context::create(); + let mut codegen = Codegen::new(&context, "test"); + let execution_engine = codegen + .module + .create_jit_execution_engine(OptimizationLevel::None) + .unwrap(); + + codegen.codegen_function("test", &[], &expr)?; + + unsafe { + let fun: JitFunction<unsafe extern "C" fn() -> T> = + execution_engine.get_function("test")?; + Ok(fun.call()) + } + } + + #[test] + fn add_literals() { + assert_eq!(jit_eval::<i64>("1 + 2").unwrap(), 3); + } + + #[test] + fn variable_shadowing() { + assert_eq!( + jit_eval::<i64>("let x = 1 in (let x = 2 in x) + x").unwrap(), + 3 + ); + } + + #[test] + fn eq() { + assert_eq!( + jit_eval::<i64>("let x = 1 in if x == 1 then 2 else 4").unwrap(), + 2 + ); + } + + #[test] + fn function_call() { + let res = jit_eval::<i64>("let id = fn x = x in id 1").unwrap(); + assert_eq!(res, 1); + } + + #[test] + fn bind_tuple_pattern() { + let res = jit_eval::<i64>("let (x, y) = (1, 2) in x + y").unwrap(); + assert_eq!(res, 3); + } +} diff --git a/users/grfn/achilles/src/codegen/mod.rs b/users/grfn/achilles/src/codegen/mod.rs new file mode 100644 index 000000000000..8ef057dba04f --- /dev/null +++ b/users/grfn/achilles/src/codegen/mod.rs @@ -0,0 +1,25 @@ +pub mod llvm; + +use inkwell::execution_engine::JitFunction; +use inkwell::OptimizationLevel; +pub use llvm::*; + +use crate::ast::hir::Expr; +use crate::ast::Type; +use crate::common::Result; + +pub fn jit_eval<T>(expr: &Expr<Type>) -> Result<T> { + let context = Context::create(); + let mut codegen = Codegen::new(&context, "eval"); + let execution_engine = codegen + .module + .create_jit_execution_engine(OptimizationLevel::None) + .map_err(Error::from)?; + codegen.codegen_function("test", &[], &expr)?; + + unsafe { + let fun: JitFunction<unsafe extern "C" fn() -> T> = + execution_engine.get_function("eval").unwrap(); + Ok(fun.call()) + } +} diff --git a/users/grfn/achilles/src/commands/check.rs b/users/grfn/achilles/src/commands/check.rs new file mode 100644 index 000000000000..0bea482c1478 --- /dev/null +++ b/users/grfn/achilles/src/commands/check.rs @@ -0,0 +1,39 @@ +use clap::Clap; +use std::path::PathBuf; + +use crate::ast::Type; +use crate::{parser, tc, Result}; + +/// Typecheck a file or expression +#[derive(Clap)] +pub struct Check { + /// File to check + path: Option<PathBuf>, + + /// Expression to check + #[clap(long, short = 'e')] + expr: Option<String>, +} + +fn run_expr(expr: String) -> Result<Type<'static>> { + let (_, parsed) = parser::expr(&expr)?; + let hir_expr = tc::typecheck_expr(parsed)?; + Ok(hir_expr.type_().to_owned()) +} + +fn run_path(path: PathBuf) -> Result<Type<'static>> { + todo!() +} + +impl Check { + pub fn run(self) -> Result<()> { + let type_ = match (self.path, self.expr) { + (None, None) => Err("Must specify either a file or expression to check".into()), + (Some(_), Some(_)) => Err("Cannot specify both a file and expression to check".into()), + (None, Some(expr)) => run_expr(expr), + (Some(path), None) => run_path(path), + }?; + println!("type: {}", type_); + Ok(()) + } +} diff --git a/users/grfn/achilles/src/commands/compile.rs b/users/grfn/achilles/src/commands/compile.rs new file mode 100644 index 000000000000..be8767575ab5 --- /dev/null +++ b/users/grfn/achilles/src/commands/compile.rs @@ -0,0 +1,31 @@ +use std::path::PathBuf; + +use clap::Clap; + +use crate::common::Result; +use crate::compiler::{self, CompilerOptions}; + +/// Compile a source file +#[derive(Clap)] +pub struct Compile { + /// File to compile + file: PathBuf, + + /// Output file + #[clap(short = 'o')] + out_file: PathBuf, + + #[clap(flatten)] + options: CompilerOptions, +} + +impl Compile { + pub fn run(self) -> Result<()> { + eprintln!( + ">>> {} -> {}", + &self.file.to_string_lossy(), + self.out_file.to_string_lossy() + ); + compiler::compile_file(&self.file, &self.out_file, &self.options) + } +} diff --git a/users/grfn/achilles/src/commands/eval.rs b/users/grfn/achilles/src/commands/eval.rs new file mode 100644 index 000000000000..61a712c08a8e --- /dev/null +++ b/users/grfn/achilles/src/commands/eval.rs @@ -0,0 +1,32 @@ +use clap::Clap; + +use crate::codegen; +use crate::interpreter; +use crate::parser; +use crate::tc; +use crate::Result; + +/// Evaluate an expression and print its result +#[derive(Clap)] +pub struct Eval { + /// JIT-compile with LLVM instead of interpreting + #[clap(long)] + jit: bool, + + /// Expression to evaluate + expr: String, +} + +impl Eval { + pub fn run(self) -> Result<()> { + let (_, parsed) = parser::expr(&self.expr)?; + let hir = tc::typecheck_expr(parsed)?; + let result = if self.jit { + codegen::jit_eval::<i64>(&hir)?.into() + } else { + interpreter::eval(&hir)? + }; + println!("{}", result); + Ok(()) + } +} diff --git a/users/grfn/achilles/src/commands/mod.rs b/users/grfn/achilles/src/commands/mod.rs new file mode 100644 index 000000000000..fd0a822708c2 --- /dev/null +++ b/users/grfn/achilles/src/commands/mod.rs @@ -0,0 +1,7 @@ +pub mod check; +pub mod compile; +pub mod eval; + +pub use check::Check; +pub use compile::Compile; +pub use eval::Eval; diff --git a/users/grfn/achilles/src/common/env.rs b/users/grfn/achilles/src/common/env.rs new file mode 100644 index 000000000000..59a5e46c466f --- /dev/null +++ b/users/grfn/achilles/src/common/env.rs @@ -0,0 +1,59 @@ +use std::borrow::Borrow; +use std::collections::HashMap; +use std::hash::Hash; +use std::mem; + +/// A lexical environment +#[derive(Debug, PartialEq, Eq)] +pub struct Env<K: Eq + Hash, V>(Vec<HashMap<K, V>>); + +impl<K, V> Default for Env<K, V> +where + K: Eq + Hash, +{ + fn default() -> Self { + Self::new() + } +} + +impl<K, V> Env<K, V> +where + K: Eq + Hash, +{ + pub fn new() -> Self { + Self(vec![Default::default()]) + } + + pub fn push(&mut self) { + self.0.push(Default::default()); + } + + pub fn pop(&mut self) { + self.0.pop(); + } + + pub fn save(&mut self) -> Self { + mem::take(self) + } + + pub fn restore(&mut self, saved: Self) { + *self = saved; + } + + pub fn set(&mut self, k: K, v: V) { + self.0.last_mut().unwrap().insert(k, v); + } + + pub fn resolve<'a, Q>(&'a self, k: &Q) -> Option<&'a V> + where + K: Borrow<Q>, + Q: Hash + Eq + ?Sized, + { + for ctx in self.0.iter().rev() { + if let Some(res) = ctx.get(k) { + return Some(res); + } + } + None + } +} diff --git a/users/grfn/achilles/src/common/error.rs b/users/grfn/achilles/src/common/error.rs new file mode 100644 index 000000000000..51575a895e91 --- /dev/null +++ b/users/grfn/achilles/src/common/error.rs @@ -0,0 +1,59 @@ +use std::{io, result}; + +use thiserror::Error; + +use crate::{codegen, interpreter, parser, tc}; + +#[derive(Error, Debug)] +pub enum Error { + #[error(transparent)] + IOError(#[from] io::Error), + + #[error("Error parsing input: {0}")] + ParseError(#[from] parser::Error), + + #[error("Error evaluating expression: {0}")] + EvalError(#[from] interpreter::Error), + + #[error("Compile error: {0}")] + CodegenError(#[from] codegen::Error), + + #[error("Type error: {0}")] + TypeError(#[from] tc::Error), + + #[error("{0}")] + Message(String), +} + +impl From<String> for Error { + fn from(s: String) -> Self { + Self::Message(s) + } +} + +impl<'a> From<&'a str> for Error { + fn from(s: &'a str) -> Self { + Self::Message(s.to_owned()) + } +} + +impl<'a> From<nom::Err<nom::error::Error<&'a str>>> for Error { + fn from(e: nom::Err<nom::error::Error<&'a str>>) -> Self { + use nom::error::Error as NomError; + use nom::Err::*; + + Self::ParseError(match e { + Incomplete(i) => Incomplete(i), + Error(NomError { input, code }) => Error(NomError { + input: input.to_owned(), + code, + }), + Failure(NomError { input, code }) => Failure(NomError { + input: input.to_owned(), + code, + }), + }) + } +} + +pub type Result<T> = result::Result<T, Error>; diff --git a/users/grfn/achilles/src/common/mod.rs b/users/grfn/achilles/src/common/mod.rs new file mode 100644 index 000000000000..8368a6dd180f --- /dev/null +++ b/users/grfn/achilles/src/common/mod.rs @@ -0,0 +1,6 @@ +pub(crate) mod env; +pub(crate) mod error; +pub(crate) mod namer; + +pub use error::{Error, Result}; +pub use namer::{Namer, NamerOf}; diff --git a/users/grfn/achilles/src/common/namer.rs b/users/grfn/achilles/src/common/namer.rs new file mode 100644 index 000000000000..016e9f6ed99a --- /dev/null +++ b/users/grfn/achilles/src/common/namer.rs @@ -0,0 +1,122 @@ +use std::fmt::Display; +use std::marker::PhantomData; + +pub struct Namer<T, F> { + make_name: F, + counter: u64, + _phantom: PhantomData<T>, +} + +impl<T, F> Namer<T, F> { + pub fn new(make_name: F) -> Self { + Namer { + make_name, + counter: 0, + _phantom: PhantomData, + } + } +} + +impl Namer<String, Box<dyn Fn(u64) -> String>> { + pub fn with_prefix<T>(prefix: T) -> Self + where + T: Display + 'static, + { + Namer::new(move |i| format!("{}{}", prefix, i)).boxed() + } + + pub fn with_suffix<T>(suffix: T) -> Self + where + T: Display + 'static, + { + Namer::new(move |i| format!("{}{}", i, suffix)).boxed() + } + + pub fn alphabetic() -> Self { + Namer::new(|i| { + if i <= 26 { + std::char::from_u32((i + 96) as u32).unwrap().to_string() + } else { + format!( + "{}{}", + std::char::from_u32(((i % 26) + 96) as u32).unwrap(), + i - 26 + ) + } + }) + .boxed() + } +} + +impl<T, F> Namer<T, F> +where + F: Fn(u64) -> T, +{ + pub fn make_name(&mut self) -> T { + self.counter += 1; + (self.make_name)(self.counter) + } + + pub fn boxed(self) -> NamerOf<T> + where + F: 'static, + { + Namer { + make_name: Box::new(self.make_name), + counter: self.counter, + _phantom: self._phantom, + } + } + + pub fn map<G, U>(self, f: G) -> NamerOf<U> + where + G: Fn(T) -> U + 'static, + T: 'static, + F: 'static, + { + Namer { + counter: self.counter, + make_name: Box::new(move |x| f((self.make_name)(x))), + _phantom: PhantomData, + } + } +} + +pub type NamerOf<T> = Namer<T, Box<dyn Fn(u64) -> T>>; + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn prefix() { + let mut namer = Namer::with_prefix("t"); + assert_eq!(namer.make_name(), "t1"); + assert_eq!(namer.make_name(), "t2"); + } + + #[test] + fn suffix() { + let mut namer = Namer::with_suffix("t"); + assert_eq!(namer.make_name(), "1t"); + assert_eq!(namer.make_name(), "2t"); + } + + #[test] + fn alphabetic() { + let mut namer = Namer::alphabetic(); + assert_eq!(namer.make_name(), "a"); + assert_eq!(namer.make_name(), "b"); + (0..25).for_each(|_| { + namer.make_name(); + }); + assert_eq!(namer.make_name(), "b2"); + } + + #[test] + fn custom_callback() { + let mut namer = Namer::new(|n| n + 1); + assert_eq!(namer.make_name(), 2); + assert_eq!(namer.make_name(), 3); + } +} diff --git a/users/grfn/achilles/src/compiler.rs b/users/grfn/achilles/src/compiler.rs new file mode 100644 index 000000000000..45b215473d7f --- /dev/null +++ b/users/grfn/achilles/src/compiler.rs @@ -0,0 +1,89 @@ +use std::fmt::{self, Display}; +use std::path::Path; +use std::str::FromStr; +use std::{fs, result}; + +use clap::Clap; +use test_strategy::Arbitrary; + +use crate::codegen::{self, Codegen}; +use crate::common::Result; +use crate::passes::hir::{monomorphize, strip_positive_units}; +use crate::{parser, tc}; + +#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Arbitrary)] +pub enum OutputFormat { + LLVM, + Bitcode, +} + +impl Default for OutputFormat { + fn default() -> Self { + Self::Bitcode + } +} + +impl FromStr for OutputFormat { + type Err = String; + + fn from_str(s: &str) -> result::Result<Self, Self::Err> { + match s { + "llvm" => Ok(Self::LLVM), + "binary" => Ok(Self::Bitcode), + _ => Err(format!( + "Invalid output format {}, expected one of {{llvm, binary}}", + s + )), + } + } +} + +impl Display for OutputFormat { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + OutputFormat::LLVM => f.write_str("llvm"), + OutputFormat::Bitcode => f.write_str("binary"), + } + } +} + +#[derive(Clap, Debug, PartialEq, Eq, Default)] +pub struct CompilerOptions { + #[clap(long, short = 'f', default_value)] + format: OutputFormat, +} + +pub fn compile_file(input: &Path, output: &Path, options: &CompilerOptions) -> Result<()> { + let src = fs::read_to_string(input)?; + let (_, decls) = parser::toplevel(&src)?; + let mut decls = tc::typecheck_toplevel(decls)?; + monomorphize::run_toplevel(&mut decls); + strip_positive_units::run_toplevel(&mut decls); + + let context = codegen::Context::create(); + let mut codegen = Codegen::new( + &context, + &input + .file_stem() + .map_or("UNKNOWN".to_owned(), |s| s.to_string_lossy().into_owned()), + ); + for decl in &decls { + codegen.codegen_decl(decl)?; + } + match options.format { + OutputFormat::LLVM => codegen.print_to_file(output)?, + OutputFormat::Bitcode => codegen.binary_to_file(output)?, + } + Ok(()) +} + +#[cfg(test)] +mod tests { + use super::*; + use test_strategy::proptest; + + #[proptest] + fn output_format_display_from_str_round_trip(of: OutputFormat) { + assert_eq!(OutputFormat::from_str(&of.to_string()), Ok(of)); + } +} diff --git a/users/grfn/achilles/src/interpreter/error.rs b/users/grfn/achilles/src/interpreter/error.rs new file mode 100644 index 000000000000..268d6f479a1e --- /dev/null +++ b/users/grfn/achilles/src/interpreter/error.rs @@ -0,0 +1,19 @@ +use std::result; + +use thiserror::Error; + +use crate::ast::{Ident, Type}; + +#[derive(Debug, PartialEq, Eq, Error)] +pub enum Error { + #[error("Undefined variable {0}")] + UndefinedVariable(Ident<'static>), + + #[error("Unexpected type {actual}, expected type {expected}")] + InvalidType { + actual: Type<'static>, + expected: Type<'static>, + }, +} + +pub type Result<T> = result::Result<T, Error>; diff --git a/users/grfn/achilles/src/interpreter/mod.rs b/users/grfn/achilles/src/interpreter/mod.rs new file mode 100644 index 000000000000..70df7a0724a5 --- /dev/null +++ b/users/grfn/achilles/src/interpreter/mod.rs @@ -0,0 +1,203 @@ +mod error; +mod value; + +use itertools::Itertools; +use value::Val; + +pub use self::error::{Error, Result}; +pub use self::value::{Function, Value}; +use crate::ast::hir::{Binding, Expr, Pattern}; +use crate::ast::{BinaryOperator, FunctionType, Ident, Literal, Type, UnaryOperator}; +use crate::common::env::Env; + +#[derive(Debug, Default)] +pub struct Interpreter<'a> { + env: Env<&'a Ident<'a>, Value<'a>>, +} + +impl<'a> Interpreter<'a> { + pub fn new() -> Self { + Self::default() + } + + fn resolve(&self, var: &'a Ident<'a>) -> Result<Value<'a>> { + self.env + .resolve(var) + .cloned() + .ok_or_else(|| Error::UndefinedVariable(var.to_owned())) + } + + fn bind_pattern(&mut self, pattern: &'a Pattern<'a, Type>, value: Value<'a>) { + match pattern { + Pattern::Id(id, _) => self.env.set(id, value), + Pattern::Tuple(pats) => { + for (pat, val) in pats.iter().zip(value.as_tuple().unwrap().clone()) { + self.bind_pattern(pat, val); + } + } + } + } + + pub fn eval(&mut self, expr: &'a Expr<'a, Type>) -> Result<Value<'a>> { + let res = match expr { + Expr::Ident(id, _) => self.resolve(id), + Expr::Literal(Literal::Int(i), _) => Ok((*i).into()), + Expr::Literal(Literal::Bool(b), _) => Ok((*b).into()), + Expr::Literal(Literal::String(s), _) => Ok(s.clone().into()), + Expr::Literal(Literal::Unit, _) => unreachable!(), + Expr::UnaryOp { op, rhs, .. } => { + let rhs = self.eval(rhs)?; + match op { + UnaryOperator::Neg => -rhs, + _ => unimplemented!(), + } + } + Expr::BinaryOp { lhs, op, rhs, .. } => { + let lhs = self.eval(lhs)?; + let rhs = self.eval(rhs)?; + match op { + BinaryOperator::Add => lhs + rhs, + BinaryOperator::Sub => lhs - rhs, + BinaryOperator::Mul => lhs * rhs, + BinaryOperator::Div => lhs / rhs, + BinaryOperator::Pow => todo!(), + BinaryOperator::Equ => Ok(lhs.eq(&rhs).into()), + BinaryOperator::Neq => todo!(), + } + } + Expr::Let { bindings, body, .. } => { + self.env.push(); + for Binding { pat, body, .. } in bindings { + let val = self.eval(body)?; + self.bind_pattern(pat, val); + } + let res = self.eval(body)?; + self.env.pop(); + Ok(res) + } + Expr::If { + condition, + then, + else_, + .. + } => { + let condition = self.eval(condition)?; + if *(condition.as_type::<bool>()?) { + self.eval(then) + } else { + self.eval(else_) + } + } + Expr::Call { ref fun, args, .. } => { + let fun = self.eval(fun)?; + let expected_type = FunctionType { + args: args.iter().map(|_| Type::Int).collect(), + ret: Box::new(Type::Int), + }; + + let Function { + args: function_args, + body, + .. + } = fun.as_function(expected_type)?; + let arg_values = function_args.iter().zip( + args.iter() + .map(|v| self.eval(v)) + .collect::<Result<Vec<_>>>()?, + ); + let mut interpreter = Interpreter::new(); + for (arg_name, arg_value) in arg_values { + interpreter.env.set(arg_name, arg_value); + } + Ok(Value::from(*interpreter.eval(body)?.as_type::<i64>()?)) + } + Expr::Fun { + type_args: _, + args, + body, + type_, + } => { + let type_ = match type_ { + Type::Function(ft) => ft.clone(), + _ => unreachable!("Function expression without function type"), + }; + + Ok(Value::from(value::Function { + // TODO + type_, + args: args.iter().map(|(arg, _)| arg.to_owned()).collect(), + body: (**body).to_owned(), + })) + } + Expr::Tuple(members, _) => Ok(Val::Tuple( + members + .into_iter() + .map(|expr| self.eval(expr)) + .try_collect()?, + ) + .into()), + }?; + debug_assert_eq!(&res.type_(), expr.type_()); + Ok(res) + } +} + +pub fn eval<'a>(expr: &'a Expr<'a, Type>) -> Result<Value<'a>> { + let mut interpreter = Interpreter::new(); + interpreter.eval(expr) +} + +#[cfg(test)] +mod tests { + use std::convert::TryFrom; + + use super::value::{TypeOf, Val}; + use super::*; + use BinaryOperator::*; + + fn int_lit(i: u64) -> Box<Expr<'static, Type<'static>>> { + Box::new(Expr::Literal(Literal::Int(i), Type::Int)) + } + + fn do_eval<T>(src: &str) -> T + where + for<'a> &'a T: TryFrom<&'a Val<'a>>, + T: Clone + TypeOf, + { + let expr = crate::parser::expr(src).unwrap().1; + let hir = crate::tc::typecheck_expr(expr).unwrap(); + let res = eval(&hir).unwrap(); + res.as_type::<T>().unwrap().clone() + } + + #[test] + fn simple_addition() { + let expr = Expr::BinaryOp { + lhs: int_lit(1), + op: Mul, + rhs: int_lit(2), + type_: Type::Int, + }; + let res = eval(&expr).unwrap(); + assert_eq!(*res.as_type::<i64>().unwrap(), 2); + } + + #[test] + fn variable_shadowing() { + let res = do_eval::<i64>("let x = 1 in (let x = 2 in x) + x"); + assert_eq!(res, 3); + } + + #[test] + fn conditional_with_equals() { + let res = do_eval::<i64>("let x = 1 in if x == 1 then 2 else 4"); + assert_eq!(res, 2); + } + + #[test] + #[ignore] + fn function_call() { + let res = do_eval::<i64>("let id = fn x = x in id 1"); + assert_eq!(res, 1); + } +} diff --git a/users/grfn/achilles/src/interpreter/value.rs b/users/grfn/achilles/src/interpreter/value.rs new file mode 100644 index 000000000000..272d1167a33c --- /dev/null +++ b/users/grfn/achilles/src/interpreter/value.rs @@ -0,0 +1,224 @@ +use std::borrow::Cow; +use std::convert::TryFrom; +use std::fmt::{self, Display}; +use std::ops::{Add, Div, Mul, Neg, Sub}; +use std::rc::Rc; +use std::result; + +use derive_more::{Deref, From, TryInto}; +use itertools::Itertools; + +use super::{Error, Result}; +use crate::ast::hir::Expr; +use crate::ast::{FunctionType, Ident, Type}; + +#[derive(Debug, Clone)] +pub struct Function<'a> { + pub type_: FunctionType<'a>, + pub args: Vec<Ident<'a>>, + pub body: Expr<'a, Type<'a>>, +} + +#[derive(From, TryInto)] +#[try_into(owned, ref)] +pub enum Val<'a> { + Int(i64), + Float(f64), + Bool(bool), + String(Cow<'a, str>), + Tuple(Vec<Value<'a>>), + Function(Function<'a>), +} + +impl<'a> TryFrom<Val<'a>> for String { + type Error = (); + + fn try_from(value: Val<'a>) -> result::Result<Self, Self::Error> { + match value { + Val::String(s) => Ok(s.into_owned()), + _ => Err(()), + } + } +} + +impl<'a> fmt::Debug for Val<'a> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + Val::Int(x) => f.debug_tuple("Int").field(x).finish(), + Val::Float(x) => f.debug_tuple("Float").field(x).finish(), + Val::Bool(x) => f.debug_tuple("Bool").field(x).finish(), + Val::String(s) => f.debug_tuple("String").field(s).finish(), + Val::Function(Function { type_, .. }) => { + f.debug_struct("Function").field("type_", type_).finish() + } + Val::Tuple(members) => f.debug_tuple("Tuple").field(members).finish(), + } + } +} + +impl<'a> PartialEq for Val<'a> { + fn eq(&self, other: &Self) -> bool { + match (self, other) { + (Val::Int(x), Val::Int(y)) => x == y, + (Val::Float(x), Val::Float(y)) => x == y, + (Val::Bool(x), Val::Bool(y)) => x == y, + (Val::Function(_), Val::Function(_)) => false, + (_, _) => false, + } + } +} + +impl<'a> From<u64> for Val<'a> { + fn from(i: u64) -> Self { + Self::from(i as i64) + } +} + +impl<'a> Display for Val<'a> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + Val::Int(x) => x.fmt(f), + Val::Float(x) => x.fmt(f), + Val::Bool(x) => x.fmt(f), + Val::String(s) => write!(f, "{:?}", s), + Val::Function(Function { type_, .. }) => write!(f, "<{}>", type_), + Val::Tuple(members) => write!(f, "({})", members.iter().join(", ")), + } + } +} + +impl<'a> Val<'a> { + pub fn type_(&self) -> Type { + match self { + Val::Int(_) => Type::Int, + Val::Float(_) => Type::Float, + Val::Bool(_) => Type::Bool, + Val::String(_) => Type::CString, + Val::Function(Function { type_, .. }) => Type::Function(type_.clone()), + Val::Tuple(members) => Type::Tuple(members.iter().map(|expr| expr.type_()).collect()), + } + } + + pub fn as_type<'b, T>(&'b self) -> Result<&'b T> + where + T: TypeOf + 'b + Clone, + &'b T: TryFrom<&'b Self>, + { + <&T>::try_from(self).map_err(|_| Error::InvalidType { + actual: self.type_().to_owned(), + expected: <T as TypeOf>::type_of(), + }) + } + + pub fn as_function<'b>(&'b self, function_type: FunctionType) -> Result<&'b Function<'a>> { + match self { + Val::Function(f) if f.type_ == function_type => Ok(&f), + _ => Err(Error::InvalidType { + actual: self.type_().to_owned(), + expected: Type::Function(function_type.to_owned()), + }), + } + } + + pub fn as_tuple(&self) -> Option<&Vec<Value<'a>>> { + if let Self::Tuple(v) = self { + Some(v) + } else { + None + } + } + + pub fn try_into_tuple(self) -> result::Result<Vec<Value<'a>>, Self> { + if let Self::Tuple(v) = self { + Ok(v) + } else { + Err(self) + } + } +} + +#[derive(Debug, PartialEq, Clone, Deref)] +pub struct Value<'a>(Rc<Val<'a>>); + +impl<'a> Display for Value<'a> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + self.0.fmt(f) + } +} + +impl<'a, T> From<T> for Value<'a> +where + Val<'a>: From<T>, +{ + fn from(x: T) -> Self { + Self(Rc::new(x.into())) + } +} + +impl<'a> Neg for Value<'a> { + type Output = Result<Value<'a>>; + + fn neg(self) -> Self::Output { + Ok((-self.as_type::<i64>()?).into()) + } +} + +impl<'a> Add for Value<'a> { + type Output = Result<Value<'a>>; + + fn add(self, rhs: Self) -> Self::Output { + Ok((self.as_type::<i64>()? + rhs.as_type::<i64>()?).into()) + } +} + +impl<'a> Sub for Value<'a> { + type Output = Result<Value<'a>>; + + fn sub(self, rhs: Self) -> Self::Output { + Ok((self.as_type::<i64>()? - rhs.as_type::<i64>()?).into()) + } +} + +impl<'a> Mul for Value<'a> { + type Output = Result<Value<'a>>; + + fn mul(self, rhs: Self) -> Self::Output { + Ok((self.as_type::<i64>()? * rhs.as_type::<i64>()?).into()) + } +} + +impl<'a> Div for Value<'a> { + type Output = Result<Value<'a>>; + + fn div(self, rhs: Self) -> Self::Output { + Ok((self.as_type::<f64>()? / rhs.as_type::<f64>()?).into()) + } +} + +pub trait TypeOf { + fn type_of() -> Type<'static>; +} + +impl TypeOf for i64 { + fn type_of() -> Type<'static> { + Type::Int + } +} + +impl TypeOf for bool { + fn type_of() -> Type<'static> { + Type::Bool + } +} + +impl TypeOf for f64 { + fn type_of() -> Type<'static> { + Type::Float + } +} + +impl TypeOf for String { + fn type_of() -> Type<'static> { + Type::CString + } +} diff --git a/users/grfn/achilles/src/main.rs b/users/grfn/achilles/src/main.rs new file mode 100644 index 000000000000..5ae1b59b3a8e --- /dev/null +++ b/users/grfn/achilles/src/main.rs @@ -0,0 +1,36 @@ +use clap::Clap; + +pub mod ast; +pub mod codegen; +pub(crate) mod commands; +pub(crate) mod common; +pub mod compiler; +pub mod interpreter; +pub(crate) mod passes; +#[macro_use] +pub mod parser; +pub mod tc; + +pub use common::{Error, Result}; + +#[derive(Clap)] +struct Opts { + #[clap(subcommand)] + subcommand: Command, +} + +#[derive(Clap)] +enum Command { + Eval(commands::Eval), + Compile(commands::Compile), + Check(commands::Check), +} + +fn main() -> anyhow::Result<()> { + let opts = Opts::parse(); + match opts.subcommand { + Command::Eval(eval) => Ok(eval.run()?), + Command::Compile(compile) => Ok(compile.run()?), + Command::Check(check) => Ok(check.run()?), + } +} diff --git a/users/grfn/achilles/src/parser/expr.rs b/users/grfn/achilles/src/parser/expr.rs new file mode 100644 index 000000000000..f596b18970aa --- /dev/null +++ b/users/grfn/achilles/src/parser/expr.rs @@ -0,0 +1,718 @@ +use std::borrow::Cow; + +use nom::alt; +use nom::character::complete::{digit1, multispace0, multispace1}; +use nom::{ + call, char, complete, delimited, do_parse, flat_map, many0, map, named, opt, parse_to, + preceded, separated_list0, separated_list1, tag, tuple, +}; +use pratt::{Affix, Associativity, PrattParser, Precedence}; + +use super::util::comma; +use crate::ast::{BinaryOperator, Binding, Expr, Fun, Literal, Pattern, UnaryOperator}; +use crate::parser::{arg, ident, type_}; + +#[derive(Debug)] +enum TokenTree<'a> { + Prefix(UnaryOperator), + // Postfix(char), + Infix(BinaryOperator), + Primary(Expr<'a>), + Group(Vec<TokenTree<'a>>), +} + +named!(prefix(&str) -> TokenTree, map!(alt!( + complete!(char!('-')) => { |_| UnaryOperator::Neg } | + complete!(char!('!')) => { |_| UnaryOperator::Not } +), TokenTree::Prefix)); + +named!(infix(&str) -> TokenTree, map!(alt!( + complete!(tag!("==")) => { |_| BinaryOperator::Equ } | + complete!(tag!("!=")) => { |_| BinaryOperator::Neq } | + complete!(char!('+')) => { |_| BinaryOperator::Add } | + complete!(char!('-')) => { |_| BinaryOperator::Sub } | + complete!(char!('*')) => { |_| BinaryOperator::Mul } | + complete!(char!('/')) => { |_| BinaryOperator::Div } | + complete!(char!('^')) => { |_| BinaryOperator::Pow } +), TokenTree::Infix)); + +named!(primary(&str) -> TokenTree, alt!( + do_parse!( + multispace0 >> + char!('(') >> + multispace0 >> + group: group >> + multispace0 >> + char!(')') >> + multispace0 >> + (TokenTree::Group(group)) + ) | + delimited!(multispace0, simple_expr, multispace0) => { |s| TokenTree::Primary(s) } +)); + +named!( + rest(&str) -> Vec<(TokenTree, Vec<TokenTree>, TokenTree)>, + many0!(tuple!( + infix, + delimited!(multispace0, many0!(prefix), multispace0), + primary + // many0!(postfix) + )) +); + +named!(group(&str) -> Vec<TokenTree>, do_parse!( + prefix: many0!(prefix) + >> primary: primary + // >> postfix: many0!(postfix) + >> rest: rest + >> ({ + let mut res = prefix; + res.push(primary); + // res.append(&mut postfix); + for (infix, mut prefix, primary/*, mut postfix*/) in rest { + res.push(infix); + res.append(&mut prefix); + res.push(primary); + // res.append(&mut postfix); + } + res + }) +)); + +fn token_tree(i: &str) -> nom::IResult<&str, Vec<TokenTree>> { + group(i) +} + +struct ExprParser; + +impl<'a, I> PrattParser<I> for ExprParser +where + I: Iterator<Item = TokenTree<'a>>, +{ + type Error = pratt::NoError; + type Input = TokenTree<'a>; + type Output = Expr<'a>; + + fn query(&mut self, input: &Self::Input) -> Result<Affix, Self::Error> { + use BinaryOperator::*; + use UnaryOperator::*; + + Ok(match input { + TokenTree::Infix(Add) => Affix::Infix(Precedence(6), Associativity::Left), + TokenTree::Infix(Sub) => Affix::Infix(Precedence(6), Associativity::Left), + TokenTree::Infix(Mul) => Affix::Infix(Precedence(7), Associativity::Left), + TokenTree::Infix(Div) => Affix::Infix(Precedence(7), Associativity::Left), + TokenTree::Infix(Pow) => Affix::Infix(Precedence(8), Associativity::Right), + TokenTree::Infix(Equ) => Affix::Infix(Precedence(4), Associativity::Right), + TokenTree::Infix(Neq) => Affix::Infix(Precedence(4), Associativity::Right), + TokenTree::Prefix(Neg) => Affix::Prefix(Precedence(6)), + TokenTree::Prefix(Not) => Affix::Prefix(Precedence(6)), + TokenTree::Primary(_) => Affix::Nilfix, + TokenTree::Group(_) => Affix::Nilfix, + }) + } + + fn primary(&mut self, input: Self::Input) -> Result<Self::Output, Self::Error> { + Ok(match input { + TokenTree::Primary(expr) => expr, + TokenTree::Group(group) => self.parse(&mut group.into_iter()).unwrap(), + _ => unreachable!(), + }) + } + + fn infix( + &mut self, + lhs: Self::Output, + op: Self::Input, + rhs: Self::Output, + ) -> Result<Self::Output, Self::Error> { + let op = match op { + TokenTree::Infix(op) => op, + _ => unreachable!(), + }; + Ok(Expr::BinaryOp { + lhs: Box::new(lhs), + op, + rhs: Box::new(rhs), + }) + } + + fn prefix(&mut self, op: Self::Input, rhs: Self::Output) -> Result<Self::Output, Self::Error> { + let op = match op { + TokenTree::Prefix(op) => op, + _ => unreachable!(), + }; + + Ok(Expr::UnaryOp { + op, + rhs: Box::new(rhs), + }) + } + + fn postfix( + &mut self, + _lhs: Self::Output, + _op: Self::Input, + ) -> Result<Self::Output, Self::Error> { + unreachable!() + } +} + +named!(int(&str) -> Literal, map!(flat_map!(digit1, parse_to!(u64)), Literal::Int)); + +named!(bool_(&str) -> Literal, alt!( + complete!(tag!("true")) => { |_| Literal::Bool(true) } | + complete!(tag!("false")) => { |_| Literal::Bool(false) } +)); + +fn string_internal(i: &str) -> nom::IResult<&str, Cow<'_, str>, nom::error::Error<&str>> { + // TODO(grfn): use String::split_once when that's stable + let (s, rem) = if let Some(pos) = i.find('"') { + (&i[..pos], &i[(pos + 1)..]) + } else { + return Err(nom::Err::Error(nom::error::Error::new( + i, + nom::error::ErrorKind::Tag, + ))); + }; + + Ok((rem, Cow::Borrowed(s))) +} + +named!(string(&str) -> Literal, preceded!( + complete!(char!('"')), + map!( + string_internal, + |s| Literal::String(s) + ) +)); + +named!(unit(&str) -> Literal, map!(complete!(tag!("()")), |_| Literal::Unit)); + +named!(literal(&str) -> Literal, alt!(int | bool_ | string | unit)); + +named!(literal_expr(&str) -> Expr, map!(literal, Expr::Literal)); + +named!(tuple(&str) -> Expr, do_parse!( + complete!(tag!("(")) + >> multispace0 + >> fst: expr + >> comma + >> rest: separated_list0!( + comma, + expr + ) + >> multispace0 + >> tag!(")") + >> ({ + let mut members = Vec::with_capacity(rest.len() + 1); + members.push(fst); + members.append(&mut rest.clone()); + Expr::Tuple(members) + }) +)); + +named!(tuple_pattern(&str) -> Pattern, do_parse!( + complete!(tag!("(")) + >> multispace0 + >> pats: separated_list0!( + comma, + pattern + ) + >> multispace0 + >> tag!(")") + >> (Pattern::Tuple(pats)) +)); + +named!(pattern(&str) -> Pattern, alt!( + ident => { |id| Pattern::Id(id) } | + tuple_pattern +)); + +named!(binding(&str) -> Binding, do_parse!( + multispace0 + >> pat: pattern + >> multispace0 + >> type_: opt!(preceded!(tuple!(tag!(":"), multispace0), type_)) + >> multispace0 + >> char!('=') + >> multispace0 + >> body: expr + >> (Binding { + pat, + type_, + body + }) +)); + +named!(let_(&str) -> Expr, do_parse!( + tag!("let") + >> multispace0 + >> bindings: separated_list1!(alt!(char!(';') | char!('\n')), binding) + >> multispace0 + >> tag!("in") + >> multispace0 + >> body: expr + >> (Expr::Let { + bindings, + body: Box::new(body) + }) +)); + +named!(if_(&str) -> Expr, do_parse! ( + tag!("if") + >> multispace0 + >> condition: expr + >> multispace0 + >> tag!("then") + >> multispace0 + >> then: expr + >> multispace0 + >> tag!("else") + >> multispace0 + >> else_: expr + >> (Expr::If { + condition: Box::new(condition), + then: Box::new(then), + else_: Box::new(else_) + }) +)); + +named!(ident_expr(&str) -> Expr, map!(ident, Expr::Ident)); + +fn ascripted<'a>( + p: impl Fn(&'a str) -> nom::IResult<&'a str, Expr, nom::error::Error<&'a str>> + 'a, +) -> impl Fn(&'a str) -> nom::IResult<&str, Expr, nom::error::Error<&'a str>> { + move |i| { + do_parse!( + i, + expr: p + >> multispace0 + >> complete!(tag!(":")) + >> multispace0 + >> type_: type_ + >> (Expr::Ascription { + expr: Box::new(expr), + type_ + }) + ) + } +} + +named!(paren_expr(&str) -> Expr, + delimited!(complete!(tag!("(")), expr, complete!(tag!(")")))); + +named!(funcref(&str) -> Expr, alt!( + ident_expr | + tuple | + paren_expr +)); + +named!(no_arg_call(&str) -> Expr, do_parse!( + fun: funcref + >> complete!(tag!("()")) + >> (Expr::Call { + fun: Box::new(fun), + args: vec![], + }) +)); + +named!(fun_expr(&str) -> Expr, do_parse!( + tag!("fn") + >> multispace1 + >> args: separated_list0!(multispace1, arg) + >> multispace0 + >> char!('=') + >> multispace0 + >> body: expr + >> (Expr::Fun(Box::new(Fun { + args, + body + }))) +)); + +named!(fn_arg(&str) -> Expr, alt!( + ident_expr | + literal_expr | + tuple | + paren_expr +)); + +named!(call_with_args(&str) -> Expr, do_parse!( + fun: funcref + >> multispace1 + >> args: separated_list1!(multispace1, fn_arg) + >> (Expr::Call { + fun: Box::new(fun), + args + }) +)); + +named!(simple_expr_unascripted(&str) -> Expr, alt!( + let_ | + if_ | + fun_expr | + literal_expr | + ident_expr | + tuple +)); + +named!(simple_expr(&str) -> Expr, alt!( + call!(ascripted(simple_expr_unascripted)) | + simple_expr_unascripted +)); + +named!(pub expr(&str) -> Expr, alt!( + no_arg_call | + call_with_args | + map!(token_tree, |tt| { + ExprParser.parse(&mut tt.into_iter()).unwrap() + }) | + simple_expr +)); + +#[cfg(test)] +pub(crate) mod tests { + use super::*; + use crate::ast::{Arg, Ident, Pattern, Type}; + use std::convert::TryFrom; + use BinaryOperator::*; + use Expr::{BinaryOp, If, Let, UnaryOp}; + use UnaryOperator::*; + + pub(crate) fn ident_expr(s: &str) -> Box<Expr> { + Box::new(Expr::Ident(Ident::try_from(s).unwrap())) + } + + mod operators { + use super::*; + + #[test] + fn mul_plus() { + let (rem, res) = expr("x*y+z").unwrap(); + assert!(rem.is_empty()); + assert_eq!( + res, + BinaryOp { + lhs: Box::new(BinaryOp { + lhs: ident_expr("x"), + op: Mul, + rhs: ident_expr("y") + }), + op: Add, + rhs: ident_expr("z") + } + ) + } + + #[test] + fn mul_plus_ws() { + let (rem, res) = expr("x * y + z").unwrap(); + assert!(rem.is_empty(), "non-empty remainder: \"{}\"", rem); + assert_eq!( + res, + BinaryOp { + lhs: Box::new(BinaryOp { + lhs: ident_expr("x"), + op: Mul, + rhs: ident_expr("y") + }), + op: Add, + rhs: ident_expr("z") + } + ) + } + + #[test] + fn unary() { + let (rem, res) = expr("x * -z").unwrap(); + assert!(rem.is_empty(), "non-empty remainder: \"{}\"", rem); + assert_eq!( + res, + BinaryOp { + lhs: ident_expr("x"), + op: Mul, + rhs: Box::new(UnaryOp { + op: Neg, + rhs: ident_expr("z"), + }) + } + ) + } + + #[test] + fn mul_literal() { + let (rem, res) = expr("x * 3").unwrap(); + assert!(rem.is_empty()); + assert_eq!( + res, + BinaryOp { + lhs: ident_expr("x"), + op: Mul, + rhs: Box::new(Expr::Literal(Literal::Int(3))), + } + ) + } + + #[test] + fn equ() { + let res = test_parse!(expr, "x * 7 == 7"); + assert_eq!( + res, + BinaryOp { + lhs: Box::new(BinaryOp { + lhs: ident_expr("x"), + op: Mul, + rhs: Box::new(Expr::Literal(Literal::Int(7))) + }), + op: Equ, + rhs: Box::new(Expr::Literal(Literal::Int(7))) + } + ) + } + } + + #[test] + fn unit() { + assert_eq!(test_parse!(expr, "()"), Expr::Literal(Literal::Unit)); + } + + #[test] + fn bools() { + assert_eq!( + test_parse!(expr, "true"), + Expr::Literal(Literal::Bool(true)) + ); + assert_eq!( + test_parse!(expr, "false"), + Expr::Literal(Literal::Bool(false)) + ); + } + + #[test] + fn tuple() { + assert_eq!( + test_parse!(expr, "(1, \"seven\")"), + Expr::Tuple(vec![ + Expr::Literal(Literal::Int(1)), + Expr::Literal(Literal::String(Cow::Borrowed("seven"))) + ]) + ) + } + + #[test] + fn simple_string_lit() { + assert_eq!( + test_parse!(expr, "\"foobar\""), + Expr::Literal(Literal::String(Cow::Borrowed("foobar"))) + ) + } + + #[test] + fn let_complex() { + let res = test_parse!(expr, "let x = 1; y = x * 7 in (x + y) * 4"); + assert_eq!( + res, + Let { + bindings: vec![ + Binding { + pat: Pattern::Id(Ident::try_from("x").unwrap()), + type_: None, + body: Expr::Literal(Literal::Int(1)) + }, + Binding { + pat: Pattern::Id(Ident::try_from("y").unwrap()), + type_: None, + body: Expr::BinaryOp { + lhs: ident_expr("x"), + op: Mul, + rhs: Box::new(Expr::Literal(Literal::Int(7))) + } + } + ], + body: Box::new(Expr::BinaryOp { + lhs: Box::new(Expr::BinaryOp { + lhs: ident_expr("x"), + op: Add, + rhs: ident_expr("y"), + }), + op: Mul, + rhs: Box::new(Expr::Literal(Literal::Int(4))), + }) + } + ) + } + + #[test] + fn if_simple() { + let res = test_parse!(expr, "if x == 8 then 9 else 20"); + assert_eq!( + res, + If { + condition: Box::new(BinaryOp { + lhs: ident_expr("x"), + op: Equ, + rhs: Box::new(Expr::Literal(Literal::Int(8))), + }), + then: Box::new(Expr::Literal(Literal::Int(9))), + else_: Box::new(Expr::Literal(Literal::Int(20))) + } + ) + } + + #[test] + fn no_arg_call() { + let res = test_parse!(expr, "f()"); + assert_eq!( + res, + Expr::Call { + fun: ident_expr("f"), + args: vec![] + } + ); + } + + #[test] + fn unit_call() { + let res = test_parse!(expr, "f ()"); + assert_eq!( + res, + Expr::Call { + fun: ident_expr("f"), + args: vec![Expr::Literal(Literal::Unit)] + } + ) + } + + #[test] + fn call_with_args() { + let res = test_parse!(expr, "f x 1"); + assert_eq!( + res, + Expr::Call { + fun: ident_expr("f"), + args: vec![*ident_expr("x"), Expr::Literal(Literal::Int(1))] + } + ) + } + + #[test] + fn call_funcref() { + let res = test_parse!(expr, "(let x = 1 in x) 2"); + assert_eq!( + res, + Expr::Call { + fun: Box::new(Expr::Let { + bindings: vec![Binding { + pat: Pattern::Id(Ident::try_from("x").unwrap()), + type_: None, + body: Expr::Literal(Literal::Int(1)) + }], + body: ident_expr("x") + }), + args: vec![Expr::Literal(Literal::Int(2))] + } + ) + } + + #[test] + fn anon_function() { + let res = test_parse!(expr, "let id = fn x = x in id 1"); + assert_eq!( + res, + Expr::Let { + bindings: vec![Binding { + pat: Pattern::Id(Ident::try_from("id").unwrap()), + type_: None, + body: Expr::Fun(Box::new(Fun { + args: vec![Arg::try_from("x").unwrap()], + body: *ident_expr("x") + })) + }], + body: Box::new(Expr::Call { + fun: ident_expr("id"), + args: vec![Expr::Literal(Literal::Int(1))], + }) + } + ); + } + + #[test] + fn tuple_binding() { + let res = test_parse!(expr, "let (x, y) = (1, 2) in x"); + assert_eq!( + res, + Expr::Let { + bindings: vec![Binding { + pat: Pattern::Tuple(vec![ + Pattern::Id(Ident::from_str_unchecked("x")), + Pattern::Id(Ident::from_str_unchecked("y")) + ]), + body: Expr::Tuple(vec![ + Expr::Literal(Literal::Int(1)), + Expr::Literal(Literal::Int(2)) + ]), + type_: None + }], + body: Box::new(Expr::Ident(Ident::from_str_unchecked("x"))) + } + ) + } + + mod ascriptions { + use super::*; + + #[test] + fn bare_ascription() { + let res = test_parse!(expr, "1: float"); + assert_eq!( + res, + Expr::Ascription { + expr: Box::new(Expr::Literal(Literal::Int(1))), + type_: Type::Float + } + ) + } + + #[test] + fn fn_body_ascription() { + let res = test_parse!(expr, "let const_1 = fn x = 1: int in const_1 2"); + assert_eq!( + res, + Expr::Let { + bindings: vec![Binding { + pat: Pattern::Id(Ident::try_from("const_1").unwrap()), + type_: None, + body: Expr::Fun(Box::new(Fun { + args: vec![Arg::try_from("x").unwrap()], + body: Expr::Ascription { + expr: Box::new(Expr::Literal(Literal::Int(1))), + type_: Type::Int, + } + })) + }], + body: Box::new(Expr::Call { + fun: ident_expr("const_1"), + args: vec![Expr::Literal(Literal::Int(2))] + }) + } + ) + } + + #[test] + fn let_binding_ascripted() { + let res = test_parse!(expr, "let x: int = 1 in x"); + assert_eq!( + res, + Expr::Let { + bindings: vec![Binding { + pat: Pattern::Id(Ident::try_from("x").unwrap()), + type_: Some(Type::Int), + body: Expr::Literal(Literal::Int(1)) + }], + body: ident_expr("x") + } + ) + } + } +} diff --git a/users/grfn/achilles/src/parser/macros.rs b/users/grfn/achilles/src/parser/macros.rs new file mode 100644 index 000000000000..406e5c0e699e --- /dev/null +++ b/users/grfn/achilles/src/parser/macros.rs @@ -0,0 +1,16 @@ +#[cfg(test)] +#[macro_use] +macro_rules! test_parse { + ($parser: ident, $src: expr) => {{ + let res = $parser($src); + nom_trace::print_trace!(); + let (rem, res) = res.unwrap(); + assert!( + rem.is_empty(), + "non-empty remainder: \"{}\", parsed: {:?}", + rem, + res + ); + res + }}; +} diff --git a/users/grfn/achilles/src/parser/mod.rs b/users/grfn/achilles/src/parser/mod.rs new file mode 100644 index 000000000000..e088cbca10a5 --- /dev/null +++ b/users/grfn/achilles/src/parser/mod.rs @@ -0,0 +1,240 @@ +use nom::character::complete::{multispace0, multispace1}; +use nom::error::{ErrorKind, ParseError}; +use nom::{alt, char, complete, do_parse, eof, many0, named, separated_list0, tag, terminated}; + +#[macro_use] +pub(crate) mod macros; +mod expr; +mod type_; +mod util; + +use crate::ast::{Arg, Decl, Fun, Ident}; +pub use expr::expr; +use type_::function_type; +pub use type_::type_; + +pub type Error = nom::Err<nom::error::Error<String>>; + +pub(crate) fn is_reserved(s: &str) -> bool { + matches!( + s, + "if" | "then" + | "else" + | "let" + | "in" + | "fn" + | "ty" + | "int" + | "float" + | "bool" + | "true" + | "false" + | "cstring" + ) +} + +pub(crate) fn ident<'a, E>(i: &'a str) -> nom::IResult<&'a str, Ident, E> +where + E: ParseError<&'a str>, +{ + let mut chars = i.chars(); + if let Some(f) = chars.next() { + if f.is_alphabetic() || f == '_' { + let mut idx = 1; + for c in chars { + if !(c.is_alphanumeric() || c == '_') { + break; + } + idx += 1; + } + let id = &i[..idx]; + if is_reserved(id) { + Err(nom::Err::Error(E::from_error_kind(i, ErrorKind::Satisfy))) + } else { + Ok((&i[idx..], Ident::from_str_unchecked(id))) + } + } else { + Err(nom::Err::Error(E::from_error_kind(i, ErrorKind::Satisfy))) + } + } else { + Err(nom::Err::Error(E::from_error_kind(i, ErrorKind::Eof))) + } +} + +named!(ascripted_arg(&str) -> Arg, do_parse!( + complete!(char!('(')) >> + multispace0 >> + ident: ident >> + multispace0 >> + complete!(char!(':')) >> + multispace0 >> + type_: type_ >> + multispace0 >> + complete!(char!(')')) >> + (Arg { + ident, + type_: Some(type_) + }) +)); + +named!(arg(&str) -> Arg, alt!( + ident => { |ident| Arg {ident, type_: None}} | + ascripted_arg +)); + +named!(extern_decl(&str) -> Decl, do_parse!( + complete!(tag!("extern")) + >> multispace1 + >> name: ident + >> multispace0 + >> char!(':') + >> multispace0 + >> type_: function_type + >> multispace0 + >> (Decl::Extern { + name, + type_ + }) +)); + +named!(fun_decl(&str) -> Decl, do_parse!( + complete!(tag!("fn")) + >> multispace1 + >> name: ident + >> multispace1 + >> args: separated_list0!(multispace1, arg) + >> multispace0 + >> char!('=') + >> multispace0 + >> body: expr + >> (Decl::Fun { + name, + body: Fun { + args, + body + } + }) +)); + +named!(ascription_decl(&str) -> Decl, do_parse!( + complete!(tag!("ty")) + >> multispace1 + >> name: ident + >> multispace0 + >> complete!(char!(':')) + >> multispace0 + >> type_: type_ + >> multispace0 + >> (Decl::Ascription { + name, + type_ + }) +)); + +named!(pub decl(&str) -> Decl, alt!( + ascription_decl | + fun_decl | + extern_decl +)); + +named!(pub toplevel(&str) -> Vec<Decl>, do_parse!( + decls: many0!(decl) + >> multispace0 + >> eof!() + >> (decls))); + +#[cfg(test)] +mod tests { + use std::convert::TryInto; + + use crate::ast::{BinaryOperator, Expr, FunctionType, Literal, Type}; + + use super::*; + use expr::tests::ident_expr; + + #[test] + fn fn_decl() { + let res = test_parse!(decl, "fn id x = x"); + assert_eq!( + res, + Decl::Fun { + name: "id".try_into().unwrap(), + body: Fun { + args: vec!["x".try_into().unwrap()], + body: *ident_expr("x"), + } + } + ) + } + + #[test] + fn ascripted_fn_args() { + test_parse!(ascripted_arg, "(x : int)"); + let res = test_parse!(decl, "fn plus1 (x : int) = x + 1"); + assert_eq!( + res, + Decl::Fun { + name: "plus1".try_into().unwrap(), + body: Fun { + args: vec![Arg { + ident: "x".try_into().unwrap(), + type_: Some(Type::Int), + }], + body: Expr::BinaryOp { + lhs: ident_expr("x"), + op: BinaryOperator::Add, + rhs: Box::new(Expr::Literal(Literal::Int(1))), + } + } + } + ); + } + + #[test] + fn multiple_decls() { + let res = test_parse!( + toplevel, + "fn id x = x + fn plus x y = x + y + fn main = plus (id 2) 7" + ); + assert_eq!(res.len(), 3); + let res = test_parse!( + toplevel, + "fn id x = x\nfn plus x y = x + y\nfn main = plus (id 2) 7\n" + ); + assert_eq!(res.len(), 3); + } + + #[test] + fn top_level_ascription() { + let res = test_parse!(toplevel, "ty id : fn a -> a"); + assert_eq!( + res, + vec![Decl::Ascription { + name: "id".try_into().unwrap(), + type_: Type::Function(FunctionType { + args: vec![Type::Var("a".try_into().unwrap())], + ret: Box::new(Type::Var("a".try_into().unwrap())) + }) + }] + ) + } + + #[test] + fn return_unit() { + assert_eq!( + test_parse!(decl, "fn g _ = ()"), + Decl::Fun { + name: "g".try_into().unwrap(), + body: Fun { + args: vec![Arg { + ident: "_".try_into().unwrap(), + type_: None, + }], + body: Expr::Literal(Literal::Unit), + }, + } + ) + } +} diff --git a/users/grfn/achilles/src/parser/type_.rs b/users/grfn/achilles/src/parser/type_.rs new file mode 100644 index 000000000000..b80f0e0860a1 --- /dev/null +++ b/users/grfn/achilles/src/parser/type_.rs @@ -0,0 +1,152 @@ +use nom::character::complete::{multispace0, multispace1}; +use nom::{alt, delimited, do_parse, map, named, opt, separated_list0, tag, terminated, tuple}; + +use super::ident; +use super::util::comma; +use crate::ast::{FunctionType, Type}; + +named!(pub function_type(&str) -> FunctionType, do_parse!( + tag!("fn") + >> multispace1 + >> args: map!(opt!(terminated!(separated_list0!( + comma, + type_ + ), multispace1)), |args| args.unwrap_or_default()) + >> tag!("->") + >> multispace1 + >> ret: type_ + >> (FunctionType { + args, + ret: Box::new(ret) + }) +)); + +named!(tuple_type(&str) -> Type, do_parse!( + tag!("(") + >> multispace0 + >> fst: type_ + >> comma + >> rest: separated_list0!( + comma, + type_ + ) + >> multispace0 + >> tag!(")") + >> ({ + let mut members = Vec::with_capacity(rest.len() + 1); + members.push(fst); + members.append(&mut rest.clone()); + Type::Tuple(members) + }) +)); + +named!(pub type_(&str) -> Type, alt!( + tag!("int") => { |_| Type::Int } | + tag!("float") => { |_| Type::Float } | + tag!("bool") => { |_| Type::Bool } | + tag!("cstring") => { |_| Type::CString } | + tag!("()") => { |_| Type::Unit } | + tuple_type | + function_type => { |ft| Type::Function(ft) }| + ident => { |id| Type::Var(id) } | + delimited!( + tuple!(tag!("("), multispace0), + type_, + tuple!(tag!(")"), multispace0) + ) +)); + +#[cfg(test)] +mod tests { + use std::convert::TryFrom; + + use super::*; + use crate::ast::Ident; + + #[test] + fn simple_types() { + assert_eq!(test_parse!(type_, "int"), Type::Int); + assert_eq!(test_parse!(type_, "float"), Type::Float); + assert_eq!(test_parse!(type_, "bool"), Type::Bool); + assert_eq!(test_parse!(type_, "cstring"), Type::CString); + assert_eq!(test_parse!(type_, "()"), Type::Unit); + } + + #[test] + fn no_arg_fn_type() { + assert_eq!( + test_parse!(type_, "fn -> int"), + Type::Function(FunctionType { + args: vec![], + ret: Box::new(Type::Int) + }) + ); + } + + #[test] + fn fn_type_with_args() { + assert_eq!( + test_parse!(type_, "fn int, bool -> int"), + Type::Function(FunctionType { + args: vec![Type::Int, Type::Bool], + ret: Box::new(Type::Int) + }) + ); + } + + #[test] + fn fn_taking_fn() { + assert_eq!( + test_parse!(type_, "fn fn int, bool -> bool, float -> float"), + Type::Function(FunctionType { + args: vec![ + Type::Function(FunctionType { + args: vec![Type::Int, Type::Bool], + ret: Box::new(Type::Bool) + }), + Type::Float + ], + ret: Box::new(Type::Float) + }) + ) + } + + #[test] + fn parenthesized() { + assert_eq!( + test_parse!(type_, "fn (fn int, bool -> bool), float -> float"), + Type::Function(FunctionType { + args: vec![ + Type::Function(FunctionType { + args: vec![Type::Int, Type::Bool], + ret: Box::new(Type::Bool) + }), + Type::Float + ], + ret: Box::new(Type::Float) + }) + ) + } + + #[test] + fn tuple() { + assert_eq!( + test_parse!(type_, "(int, int)"), + Type::Tuple(vec![Type::Int, Type::Int]) + ) + } + + #[test] + fn type_vars() { + assert_eq!( + test_parse!(type_, "fn x, y -> x"), + Type::Function(FunctionType { + args: vec![ + Type::Var(Ident::try_from("x").unwrap()), + Type::Var(Ident::try_from("y").unwrap()), + ], + ret: Box::new(Type::Var(Ident::try_from("x").unwrap())), + }) + ) + } +} diff --git a/users/grfn/achilles/src/parser/util.rs b/users/grfn/achilles/src/parser/util.rs new file mode 100644 index 000000000000..bb53fb7fff50 --- /dev/null +++ b/users/grfn/achilles/src/parser/util.rs @@ -0,0 +1,8 @@ +use nom::character::complete::multispace0; +use nom::{complete, map, named, tag, tuple}; + +named!(pub(crate) comma(&str) -> (), map!(tuple!( + multispace0, + complete!(tag!(",")), + multispace0 +) ,|_| ())); diff --git a/users/grfn/achilles/src/passes/hir/mod.rs b/users/grfn/achilles/src/passes/hir/mod.rs new file mode 100644 index 000000000000..872c449eb020 --- /dev/null +++ b/users/grfn/achilles/src/passes/hir/mod.rs @@ -0,0 +1,211 @@ +use std::collections::HashMap; + +use crate::ast::hir::{Binding, Decl, Expr, Pattern}; +use crate::ast::{BinaryOperator, Ident, Literal, UnaryOperator}; + +pub(crate) mod monomorphize; +pub(crate) mod strip_positive_units; + +pub(crate) trait Visitor<'a, 'ast, T: 'ast>: Sized + 'a { + type Error; + + fn visit_type(&mut self, _type: &mut T) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_ident(&mut self, _ident: &mut Ident<'ast>) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_literal(&mut self, _literal: &mut Literal<'ast>) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_unary_operator(&mut self, _op: &mut UnaryOperator) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_binary_operator(&mut self, _op: &mut BinaryOperator) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_pattern(&mut self, _pat: &mut Pattern<'ast, T>) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_binding(&mut self, binding: &mut Binding<'ast, T>) -> Result<(), Self::Error> { + self.visit_pattern(&mut binding.pat)?; + self.visit_expr(&mut binding.body)?; + Ok(()) + } + + fn post_visit_call( + &mut self, + _fun: &mut Expr<'ast, T>, + _type_args: &mut HashMap<Ident<'ast>, T>, + _args: &mut Vec<Expr<'ast, T>>, + ) -> Result<(), Self::Error> { + Ok(()) + } + + fn pre_visit_call( + &mut self, + _fun: &mut Expr<'ast, T>, + _type_args: &mut HashMap<Ident<'ast>, T>, + _args: &mut Vec<Expr<'ast, T>>, + ) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_tuple(&mut self, members: &mut Vec<Expr<'ast, T>>) -> Result<(), Self::Error> { + for expr in members { + self.visit_expr(expr)?; + } + Ok(()) + } + + fn pre_visit_expr(&mut self, _expr: &mut Expr<'ast, T>) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_expr(&mut self, expr: &mut Expr<'ast, T>) -> Result<(), Self::Error> { + self.pre_visit_expr(expr)?; + match expr { + Expr::Ident(id, t) => { + self.visit_ident(id)?; + self.visit_type(t)?; + } + Expr::Literal(lit, t) => { + self.visit_literal(lit)?; + self.visit_type(t)?; + } + Expr::UnaryOp { op, rhs, type_ } => { + self.visit_unary_operator(op)?; + self.visit_expr(rhs)?; + self.visit_type(type_)?; + } + Expr::BinaryOp { + lhs, + op, + rhs, + type_, + } => { + self.visit_expr(lhs)?; + self.visit_binary_operator(op)?; + self.visit_expr(rhs)?; + self.visit_type(type_)?; + } + Expr::Let { + bindings, + body, + type_, + } => { + for binding in bindings.iter_mut() { + self.visit_binding(binding)?; + } + self.visit_expr(body)?; + self.visit_type(type_)?; + } + Expr::If { + condition, + then, + else_, + type_, + } => { + self.visit_expr(condition)?; + self.visit_expr(then)?; + self.visit_expr(else_)?; + self.visit_type(type_)?; + } + Expr::Fun { + args, + body, + type_args, + type_, + } => { + for (ident, t) in args { + self.visit_ident(ident)?; + self.visit_type(t)?; + } + for ta in type_args { + self.visit_ident(ta)?; + } + self.visit_expr(body)?; + self.visit_type(type_)?; + } + Expr::Call { + fun, + args, + type_args, + type_, + } => { + self.pre_visit_call(fun, type_args, args)?; + self.visit_expr(fun)?; + for arg in args.iter_mut() { + self.visit_expr(arg)?; + } + self.visit_type(type_)?; + self.post_visit_call(fun, type_args, args)?; + } + Expr::Tuple(tup, type_) => { + self.visit_tuple(tup)?; + self.visit_type(type_)?; + } + } + + Ok(()) + } + + fn post_visit_decl(&mut self, _decl: &'a Decl<'ast, T>) -> Result<(), Self::Error> { + Ok(()) + } + + fn post_visit_fun_decl( + &mut self, + _name: &mut Ident<'ast>, + _type_args: &mut Vec<Ident>, + _args: &mut Vec<(Ident, T)>, + _body: &mut Box<Expr<T>>, + _type_: &mut T, + ) -> Result<(), Self::Error> { + Ok(()) + } + + fn visit_decl(&mut self, decl: &'a mut Decl<'ast, T>) -> Result<(), Self::Error> { + match decl { + Decl::Fun { + name, + type_args, + args, + body, + type_, + } => { + self.visit_ident(name)?; + for type_arg in type_args.iter_mut() { + self.visit_ident(type_arg)?; + } + for (arg, t) in args.iter_mut() { + self.visit_ident(arg)?; + self.visit_type(t)?; + } + self.visit_expr(body)?; + self.visit_type(type_)?; + self.post_visit_fun_decl(name, type_args, args, body, type_)?; + } + Decl::Extern { + name, + arg_types, + ret_type, + } => { + self.visit_ident(name)?; + for arg_t in arg_types { + self.visit_type(arg_t)?; + } + self.visit_type(ret_type)?; + } + } + + self.post_visit_decl(decl)?; + Ok(()) + } +} diff --git a/users/grfn/achilles/src/passes/hir/monomorphize.rs b/users/grfn/achilles/src/passes/hir/monomorphize.rs new file mode 100644 index 000000000000..251a988f4f6f --- /dev/null +++ b/users/grfn/achilles/src/passes/hir/monomorphize.rs @@ -0,0 +1,139 @@ +use std::cell::RefCell; +use std::collections::{HashMap, HashSet}; +use std::convert::TryInto; +use std::mem; + +use void::{ResultVoidExt, Void}; + +use crate::ast::hir::{Decl, Expr}; +use crate::ast::{self, Ident}; + +use super::Visitor; + +#[derive(Default)] +pub(crate) struct Monomorphize<'a, 'ast> { + decls: HashMap<&'a Ident<'ast>, &'a Decl<'ast, ast::Type<'ast>>>, + extra_decls: Vec<Decl<'ast, ast::Type<'ast>>>, + remove_decls: HashSet<Ident<'ast>>, +} + +impl<'a, 'ast> Monomorphize<'a, 'ast> { + pub(crate) fn new() -> Self { + Default::default() + } +} + +impl<'a, 'ast> Visitor<'a, 'ast, ast::Type<'ast>> for Monomorphize<'a, 'ast> { + type Error = Void; + + fn post_visit_call( + &mut self, + fun: &mut Expr<'ast, ast::Type<'ast>>, + type_args: &mut HashMap<Ident<'ast>, ast::Type<'ast>>, + args: &mut Vec<Expr<'ast, ast::Type<'ast>>>, + ) -> Result<(), Self::Error> { + let new_fun = match fun { + Expr::Ident(id, _) => { + let decl: Decl<_> = (**self.decls.get(id).unwrap()).clone(); + let name = RefCell::new(id.to_string()); + let type_args = mem::take(type_args); + let mut monomorphized = decl + .traverse_type(|ty| -> Result<_, Void> { + Ok(ty.clone().traverse_type_vars(|v| { + let concrete = type_args.get(&v).unwrap(); + name.borrow_mut().push_str(&concrete.to_string()); + concrete.clone() + })) + }) + .void_unwrap(); + let name: Ident = name.into_inner().try_into().unwrap(); + if name != *id { + self.remove_decls.insert(id.clone()); + monomorphized.set_name(name.clone()); + let type_ = monomorphized.type_().unwrap().clone(); + self.extra_decls.push(monomorphized); + Some(Expr::Ident(name, type_)) + } else { + None + } + } + _ => todo!(), + }; + if let Some(new_fun) = new_fun { + *fun = new_fun; + } + Ok(()) + } + + fn post_visit_decl( + &mut self, + decl: &'a Decl<'ast, ast::Type<'ast>>, + ) -> Result<(), Self::Error> { + self.decls.insert(decl.name(), decl); + Ok(()) + } +} + +pub(crate) fn run_toplevel<'a>(toplevel: &mut Vec<Decl<'a, ast::Type<'a>>>) { + let mut pass = Monomorphize::new(); + for decl in toplevel.iter_mut() { + pass.visit_decl(decl).void_unwrap(); + } + let remove_decls = mem::take(&mut pass.remove_decls); + let mut extra_decls = mem::take(&mut pass.extra_decls); + toplevel.retain(|decl| !remove_decls.contains(decl.name())); + extra_decls.append(toplevel); + *toplevel = extra_decls; +} + +#[cfg(test)] +mod tests { + use std::convert::TryFrom; + + use super::*; + use crate::parser::toplevel; + use crate::tc::typecheck_toplevel; + + #[test] + fn call_id_decl() { + let (_, program) = toplevel( + "ty id : fn a -> a + fn id x = x + + ty main : fn -> int + fn main = id 0", + ) + .unwrap(); + let mut program = typecheck_toplevel(program).unwrap(); + run_toplevel(&mut program); + + let find_decl = |ident: &str| { + program.iter().find(|decl| { + matches!(decl, Decl::Fun {name, ..} if name == &Ident::try_from(ident).unwrap()) + }).unwrap() + }; + + let main = find_decl("main"); + let body = match main { + Decl::Fun { body, .. } => body, + _ => unreachable!(), + }; + + let expected_type = ast::Type::Function(ast::FunctionType { + args: vec![ast::Type::Int], + ret: Box::new(ast::Type::Int), + }); + + match &**body { + Expr::Call { fun, .. } => { + let fun = match &**fun { + Expr::Ident(fun, _) => fun, + _ => unreachable!(), + }; + let called_decl = find_decl(fun.into()); + assert_eq!(called_decl.type_().unwrap(), &expected_type); + } + _ => unreachable!(), + } + } +} diff --git a/users/grfn/achilles/src/passes/hir/strip_positive_units.rs b/users/grfn/achilles/src/passes/hir/strip_positive_units.rs new file mode 100644 index 000000000000..85ee1cce4859 --- /dev/null +++ b/users/grfn/achilles/src/passes/hir/strip_positive_units.rs @@ -0,0 +1,191 @@ +use std::collections::HashMap; +use std::mem; + +use ast::hir::{Binding, Pattern}; +use ast::Literal; +use void::{ResultVoidExt, Void}; + +use crate::ast::hir::{Decl, Expr}; +use crate::ast::{self, Ident}; + +use super::Visitor; + +/// Strip all values with a unit type in positive (non-return) position +pub(crate) struct StripPositiveUnits {} + +impl<'a, 'ast> Visitor<'a, 'ast, ast::Type<'ast>> for StripPositiveUnits { + type Error = Void; + + fn pre_visit_expr( + &mut self, + expr: &mut Expr<'ast, ast::Type<'ast>>, + ) -> Result<(), Self::Error> { + let mut extracted = vec![]; + if let Expr::Call { args, .. } = expr { + // TODO(grfn): replace with drain_filter once it's stabilized + let mut i = 0; + while i != args.len() { + if args[i].type_() == &ast::Type::Unit { + let expr = args.remove(i); + if !matches!(expr, Expr::Literal(Literal::Unit, _)) { + extracted.push(expr) + }; + } else { + i += 1 + } + } + } + + if !extracted.is_empty() { + let body = mem::replace(expr, Expr::Literal(Literal::Unit, ast::Type::Unit)); + *expr = Expr::Let { + bindings: extracted + .into_iter() + .map(|expr| Binding { + pat: Pattern::Id( + Ident::from_str_unchecked("___discarded"), + expr.type_().clone(), + ), + body: expr, + }) + .collect(), + type_: body.type_().clone(), + body: Box::new(body), + }; + } + + Ok(()) + } + + fn post_visit_call( + &mut self, + _fun: &mut Expr<'ast, ast::Type<'ast>>, + _type_args: &mut HashMap<Ident<'ast>, ast::Type<'ast>>, + args: &mut Vec<Expr<'ast, ast::Type<'ast>>>, + ) -> Result<(), Self::Error> { + args.retain(|arg| arg.type_() != &ast::Type::Unit); + Ok(()) + } + + fn visit_type(&mut self, type_: &mut ast::Type<'ast>) -> Result<(), Self::Error> { + if let ast::Type::Function(ft) = type_ { + ft.args.retain(|a| a != &ast::Type::Unit); + } + Ok(()) + } + + fn post_visit_fun_decl( + &mut self, + _name: &mut Ident<'ast>, + _type_args: &mut Vec<Ident>, + args: &mut Vec<(Ident, ast::Type<'ast>)>, + _body: &mut Box<Expr<ast::Type<'ast>>>, + _type_: &mut ast::Type<'ast>, + ) -> Result<(), Self::Error> { + args.retain(|(_, ty)| ty != &ast::Type::Unit); + Ok(()) + } +} + +pub(crate) fn run_toplevel<'a>(toplevel: &mut Vec<Decl<'a, ast::Type<'a>>>) { + let mut pass = StripPositiveUnits {}; + for decl in toplevel.iter_mut() { + pass.visit_decl(decl).void_unwrap(); + } +} + +#[cfg(test)] +mod tests { + use super::*; + use crate::parser::toplevel; + use crate::tc::typecheck_toplevel; + use pretty_assertions::assert_eq; + + #[test] + fn unit_only_arg() { + let (_, program) = toplevel( + "ty f : fn () -> int + fn f _ = 1 + + ty main : fn -> int + fn main = f ()", + ) + .unwrap(); + + let (_, expected) = toplevel( + "ty f : fn -> int + fn f = 1 + + ty main : fn -> int + fn main = f()", + ) + .unwrap(); + let expected = typecheck_toplevel(expected).unwrap(); + + let mut program = typecheck_toplevel(program).unwrap(); + run_toplevel(&mut program); + + assert_eq!(program, expected); + } + + #[test] + fn unit_and_other_arg() { + let (_, program) = toplevel( + "ty f : fn (), int -> int + fn f _ x = x + + ty main : fn -> int + fn main = f () 1", + ) + .unwrap(); + + let (_, expected) = toplevel( + "ty f : fn int -> int + fn f x = x + + ty main : fn -> int + fn main = f 1", + ) + .unwrap(); + let expected = typecheck_toplevel(expected).unwrap(); + + let mut program = typecheck_toplevel(program).unwrap(); + run_toplevel(&mut program); + + assert_eq!(program, expected); + } + + #[test] + fn unit_expr_and_other_arg() { + let (_, program) = toplevel( + "ty f : fn (), int -> int + fn f _ x = x + + ty g : fn int -> () + fn g _ = () + + ty main : fn -> int + fn main = f (g 2) 1", + ) + .unwrap(); + + let (_, expected) = toplevel( + "ty f : fn int -> int + fn f x = x + + ty g : fn int -> () + fn g _ = () + + ty main : fn -> int + fn main = let ___discarded = g 2 in f 1", + ) + .unwrap(); + assert_eq!(expected.len(), 6); + let expected = typecheck_toplevel(expected).unwrap(); + + let mut program = typecheck_toplevel(program).unwrap(); + run_toplevel(&mut program); + + assert_eq!(program, expected); + } +} diff --git a/users/grfn/achilles/src/passes/mod.rs b/users/grfn/achilles/src/passes/mod.rs new file mode 100644 index 000000000000..306869bef1d5 --- /dev/null +++ b/users/grfn/achilles/src/passes/mod.rs @@ -0,0 +1 @@ +pub(crate) mod hir; diff --git a/users/grfn/achilles/src/tc/mod.rs b/users/grfn/achilles/src/tc/mod.rs new file mode 100644 index 000000000000..5825bab1fbe9 --- /dev/null +++ b/users/grfn/achilles/src/tc/mod.rs @@ -0,0 +1,808 @@ +use bimap::BiMap; +use derive_more::From; +use itertools::Itertools; +use std::cell::RefCell; +use std::collections::HashMap; +use std::convert::{TryFrom, TryInto}; +use std::fmt::{self, Display}; +use std::{mem, result}; +use thiserror::Error; + +use crate::ast::{self, hir, Arg, BinaryOperator, Ident, Literal, Pattern}; +use crate::common::env::Env; +use crate::common::{Namer, NamerOf}; + +#[derive(Debug, Error)] +pub enum Error { + #[error("Undefined variable {0}")] + UndefinedVariable(Ident<'static>), + + #[error("Mismatched types: expected {expected}, but got {actual}")] + TypeMismatch { expected: Type, actual: Type }, + + #[error("Mismatched types, expected numeric type, but got {0}")] + NonNumeric(Type), + + #[error("Ambiguous type {0}")] + AmbiguousType(TyVar), +} + +pub type Result<T> = result::Result<T, Error>; + +#[derive(Debug, PartialEq, Eq, Clone, Copy, Hash)] +pub struct TyVar(u64); + +impl Display for TyVar { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "t{}", self.0) + } +} + +#[derive(Debug, PartialEq, Eq, Clone, Hash)] +pub struct NullaryType(String); + +impl Display for NullaryType { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.write_str(&self.0) + } +} + +#[derive(Debug, PartialEq, Eq, Clone, Copy)] +pub enum PrimType { + Int, + Float, + Bool, + CString, +} + +impl<'a> From<PrimType> for ast::Type<'a> { + fn from(pr: PrimType) -> Self { + match pr { + PrimType::Int => ast::Type::Int, + PrimType::Float => ast::Type::Float, + PrimType::Bool => ast::Type::Bool, + PrimType::CString => ast::Type::CString, + } + } +} + +impl Display for PrimType { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + PrimType::Int => f.write_str("int"), + PrimType::Float => f.write_str("float"), + PrimType::Bool => f.write_str("bool"), + PrimType::CString => f.write_str("cstring"), + } + } +} + +#[derive(Debug, PartialEq, Eq, Clone, From)] +pub enum Type { + #[from(ignore)] + Univ(TyVar), + #[from(ignore)] + Exist(TyVar), + Nullary(NullaryType), + Prim(PrimType), + Tuple(Vec<Type>), + Unit, + Fun { + args: Vec<Type>, + ret: Box<Type>, + }, +} + +impl<'a> TryFrom<Type> for ast::Type<'a> { + type Error = Type; + + fn try_from(value: Type) -> result::Result<Self, Self::Error> { + match value { + Type::Unit => Ok(ast::Type::Unit), + Type::Univ(_) => todo!(), + Type::Exist(_) => Err(value), + Type::Nullary(_) => todo!(), + Type::Prim(p) => Ok(p.into()), + Type::Tuple(members) => Ok(ast::Type::Tuple( + members.into_iter().map(|ty| ty.try_into()).try_collect()?, + )), + Type::Fun { ref args, ref ret } => Ok(ast::Type::Function(ast::FunctionType { + args: args + .clone() + .into_iter() + .map(Self::try_from) + .try_collect() + .map_err(|_| value.clone())?, + ret: Box::new((*ret.clone()).try_into().map_err(|_| value.clone())?), + })), + } + } +} + +const INT: Type = Type::Prim(PrimType::Int); +const FLOAT: Type = Type::Prim(PrimType::Float); +const BOOL: Type = Type::Prim(PrimType::Bool); +const CSTRING: Type = Type::Prim(PrimType::CString); + +impl Display for Type { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + match self { + Type::Nullary(nt) => nt.fmt(f), + Type::Prim(p) => p.fmt(f), + Type::Univ(TyVar(n)) => write!(f, "∀{}", n), + Type::Exist(TyVar(n)) => write!(f, "∃{}", n), + Type::Fun { args, ret } => write!(f, "fn {} -> {}", args.iter().join(", "), ret), + Type::Tuple(members) => write!(f, "({})", members.iter().join(", ")), + Type::Unit => write!(f, "()"), + } + } +} + +struct Typechecker<'ast> { + ty_var_namer: NamerOf<TyVar>, + ctx: HashMap<TyVar, Type>, + env: Env<Ident<'ast>, Type>, + + /// AST type var -> type + instantiations: Env<Ident<'ast>, Type>, + + /// AST type-var -> universal TyVar + type_vars: RefCell<(BiMap<Ident<'ast>, TyVar>, NamerOf<Ident<'static>>)>, +} + +impl<'ast> Typechecker<'ast> { + fn new() -> Self { + Self { + ty_var_namer: Namer::new(TyVar).boxed(), + type_vars: RefCell::new(( + Default::default(), + Namer::alphabetic().map(|n| Ident::try_from(n).unwrap()), + )), + ctx: Default::default(), + env: Default::default(), + instantiations: Default::default(), + } + } + + fn bind_pattern( + &mut self, + pat: Pattern<'ast>, + type_: Type, + ) -> Result<hir::Pattern<'ast, Type>> { + match pat { + Pattern::Id(ident) => { + self.env.set(ident.clone(), type_.clone()); + Ok(hir::Pattern::Id(ident, type_)) + } + Pattern::Tuple(members) => { + let mut tys = Vec::with_capacity(members.len()); + let mut hir_members = Vec::with_capacity(members.len()); + for pat in members { + let ty = self.fresh_ex(); + hir_members.push(self.bind_pattern(pat, ty.clone())?); + tys.push(ty); + } + let tuple_type = Type::Tuple(tys); + self.unify(&tuple_type, &type_)?; + Ok(hir::Pattern::Tuple(hir_members)) + } + } + } + + pub(crate) fn tc_expr(&mut self, expr: ast::Expr<'ast>) -> Result<hir::Expr<'ast, Type>> { + match expr { + ast::Expr::Ident(ident) => { + let type_ = self + .env + .resolve(&ident) + .ok_or_else(|| Error::UndefinedVariable(ident.to_owned()))? + .clone(); + Ok(hir::Expr::Ident(ident, type_)) + } + ast::Expr::Literal(lit) => { + let type_ = match lit { + Literal::Int(_) => Type::Prim(PrimType::Int), + Literal::Bool(_) => Type::Prim(PrimType::Bool), + Literal::String(_) => Type::Prim(PrimType::CString), + Literal::Unit => Type::Unit, + }; + Ok(hir::Expr::Literal(lit.to_owned(), type_)) + } + ast::Expr::Tuple(members) => { + let members = members + .into_iter() + .map(|expr| self.tc_expr(expr)) + .collect::<Result<Vec<_>>>()?; + let type_ = Type::Tuple(members.iter().map(|expr| expr.type_().clone()).collect()); + Ok(hir::Expr::Tuple(members, type_)) + } + ast::Expr::UnaryOp { op, rhs } => todo!(), + ast::Expr::BinaryOp { lhs, op, rhs } => { + let lhs = self.tc_expr(*lhs)?; + let rhs = self.tc_expr(*rhs)?; + let type_ = match op { + BinaryOperator::Equ | BinaryOperator::Neq => { + self.unify(lhs.type_(), rhs.type_())?; + Type::Prim(PrimType::Bool) + } + BinaryOperator::Add | BinaryOperator::Sub | BinaryOperator::Mul => { + let ty = self.unify(lhs.type_(), rhs.type_())?; + // if !matches!(ty, Type::Int | Type::Float) { + // return Err(Error::NonNumeric(ty)); + // } + ty + } + BinaryOperator::Div => todo!(), + BinaryOperator::Pow => todo!(), + }; + Ok(hir::Expr::BinaryOp { + lhs: Box::new(lhs), + op, + rhs: Box::new(rhs), + type_, + }) + } + ast::Expr::Let { bindings, body } => { + self.env.push(); + let bindings = bindings + .into_iter() + .map( + |ast::Binding { pat, type_, body }| -> Result<hir::Binding<Type>> { + let body = self.tc_expr(body)?; + if let Some(type_) = type_ { + let type_ = self.type_from_ast_type(type_); + self.unify(body.type_(), &type_)?; + } + let pat = self.bind_pattern(pat, body.type_().clone())?; + Ok(hir::Binding { pat, body }) + }, + ) + .collect::<Result<Vec<hir::Binding<Type>>>>()?; + let body = self.tc_expr(*body)?; + self.env.pop(); + Ok(hir::Expr::Let { + bindings, + type_: body.type_().clone(), + body: Box::new(body), + }) + } + ast::Expr::If { + condition, + then, + else_, + } => { + let condition = self.tc_expr(*condition)?; + self.unify(&Type::Prim(PrimType::Bool), condition.type_())?; + let then = self.tc_expr(*then)?; + let else_ = self.tc_expr(*else_)?; + let type_ = self.unify(then.type_(), else_.type_())?; + Ok(hir::Expr::If { + condition: Box::new(condition), + then: Box::new(then), + else_: Box::new(else_), + type_, + }) + } + ast::Expr::Fun(f) => { + let ast::Fun { args, body } = *f; + self.env.push(); + let args: Vec<_> = args + .into_iter() + .map(|Arg { ident, type_ }| { + let ty = match type_ { + Some(t) => self.type_from_ast_type(t), + None => self.fresh_ex(), + }; + self.env.set(ident.clone(), ty.clone()); + (ident, ty) + }) + .collect(); + let body = self.tc_expr(body)?; + self.env.pop(); + Ok(hir::Expr::Fun { + type_: Type::Fun { + args: args.iter().map(|(_, ty)| ty.clone()).collect(), + ret: Box::new(body.type_().clone()), + }, + type_args: vec![], // TODO fill in once we do let generalization + args, + body: Box::new(body), + }) + } + ast::Expr::Call { fun, args } => { + let ret_ty = self.fresh_ex(); + let arg_tys = args.iter().map(|_| self.fresh_ex()).collect::<Vec<_>>(); + let ft = Type::Fun { + args: arg_tys.clone(), + ret: Box::new(ret_ty.clone()), + }; + let fun = self.tc_expr(*fun)?; + self.instantiations.push(); + self.unify(&ft, fun.type_())?; + let args = args + .into_iter() + .zip(arg_tys) + .map(|(arg, ty)| { + let arg = self.tc_expr(arg)?; + self.unify(&ty, arg.type_())?; + Ok(arg) + }) + .try_collect()?; + let type_args = self.commit_instantiations(); + Ok(hir::Expr::Call { + fun: Box::new(fun), + type_args, + args, + type_: ret_ty, + }) + } + ast::Expr::Ascription { expr, type_ } => { + let expr = self.tc_expr(*expr)?; + let type_ = self.type_from_ast_type(type_); + self.unify(expr.type_(), &type_)?; + Ok(expr) + } + } + } + + pub(crate) fn tc_decl( + &mut self, + decl: ast::Decl<'ast>, + ) -> Result<Option<hir::Decl<'ast, Type>>> { + match decl { + ast::Decl::Fun { name, body } => { + let mut expr = ast::Expr::Fun(Box::new(body)); + if let Some(type_) = self.env.resolve(&name) { + expr = ast::Expr::Ascription { + expr: Box::new(expr), + type_: self.finalize_type(type_.clone())?, + }; + } + + self.env.push(); + let body = self.tc_expr(expr)?; + let type_ = body.type_().clone(); + self.env.set(name.clone(), type_); + self.env.pop(); + match body { + hir::Expr::Fun { + type_args, + args, + body, + type_, + } => Ok(Some(hir::Decl::Fun { + name, + type_args, + args, + body, + type_, + })), + _ => unreachable!(), + } + } + ast::Decl::Ascription { name, type_ } => { + let type_ = self.type_from_ast_type(type_); + self.env.set(name.clone(), type_); + Ok(None) + } + ast::Decl::Extern { name, type_ } => { + let type_ = self.type_from_ast_type(ast::Type::Function(type_)); + self.env.set(name.clone(), type_.clone()); + let (arg_types, ret_type) = match type_ { + Type::Fun { args, ret } => (args, *ret), + _ => unreachable!(), + }; + Ok(Some(hir::Decl::Extern { + name, + arg_types, + ret_type, + })) + } + } + } + + fn fresh_tv(&mut self) -> TyVar { + self.ty_var_namer.make_name() + } + + fn fresh_ex(&mut self) -> Type { + Type::Exist(self.fresh_tv()) + } + + fn fresh_univ(&mut self) -> Type { + Type::Univ(self.fresh_tv()) + } + + fn unify(&mut self, ty1: &Type, ty2: &Type) -> Result<Type> { + match (ty1, ty2) { + (Type::Unit, Type::Unit) => Ok(Type::Unit), + (Type::Exist(tv), ty) | (ty, Type::Exist(tv)) => match self.resolve_tv(*tv)? { + Some(existing_ty) if self.types_match(ty, &existing_ty) => Ok(ty.clone()), + Some(var @ ast::Type::Var(_)) => { + let var = self.type_from_ast_type(var); + self.unify(&var, ty) + } + Some(existing_ty) => match ty { + Type::Exist(_) => { + let rhs = self.type_from_ast_type(existing_ty); + self.unify(ty, &rhs) + } + _ => Err(Error::TypeMismatch { + expected: ty.clone(), + actual: self.type_from_ast_type(existing_ty), + }), + }, + None => match self.ctx.insert(*tv, ty.clone()) { + Some(existing) => self.unify(&existing, ty), + None => Ok(ty.clone()), + }, + }, + (Type::Univ(u1), Type::Univ(u2)) if u1 == u2 => Ok(ty2.clone()), + (Type::Univ(u), ty) | (ty, Type::Univ(u)) => { + let ident = self.name_univ(*u); + match self.instantiations.resolve(&ident) { + Some(existing_ty) if ty == existing_ty => Ok(ty.clone()), + Some(existing_ty) => Err(Error::TypeMismatch { + expected: ty.clone(), + actual: existing_ty.clone(), + }), + None => { + self.instantiations.set(ident, ty.clone()); + Ok(ty.clone()) + } + } + } + (Type::Prim(p1), Type::Prim(p2)) if p1 == p2 => Ok(ty2.clone()), + (Type::Tuple(t1), Type::Tuple(t2)) if t1.len() == t2.len() => { + let ts = t1 + .iter() + .zip(t2.iter()) + .map(|(t1, t2)| self.unify(t1, t2)) + .try_collect()?; + Ok(Type::Tuple(ts)) + } + ( + Type::Fun { + args: args1, + ret: ret1, + }, + Type::Fun { + args: args2, + ret: ret2, + }, + ) => { + let args = args1 + .iter() + .zip(args2) + .map(|(t1, t2)| self.unify(t1, t2)) + .try_collect()?; + let ret = self.unify(ret1, ret2)?; + Ok(Type::Fun { + args, + ret: Box::new(ret), + }) + } + (Type::Nullary(_), _) | (_, Type::Nullary(_)) => todo!(), + _ => Err(Error::TypeMismatch { + expected: ty1.clone(), + actual: ty2.clone(), + }), + } + } + + fn finalize_expr( + &self, + expr: hir::Expr<'ast, Type>, + ) -> Result<hir::Expr<'ast, ast::Type<'ast>>> { + expr.traverse_type(|ty| self.finalize_type(ty)) + } + + fn finalize_decl( + &mut self, + decl: hir::Decl<'ast, Type>, + ) -> Result<hir::Decl<'ast, ast::Type<'ast>>> { + let res = decl.traverse_type(|ty| self.finalize_type(ty))?; + if let Some(type_) = res.type_() { + let ty = self.type_from_ast_type(type_.clone()); + self.env.set(res.name().clone(), ty); + } + Ok(res) + } + + fn finalize_type(&self, ty: Type) -> Result<ast::Type<'static>> { + let ret = match ty { + Type::Exist(tv) => self.resolve_tv(tv)?.ok_or(Error::AmbiguousType(tv)), + Type::Univ(tv) => Ok(ast::Type::Var(self.name_univ(tv))), + Type::Unit => Ok(ast::Type::Unit), + Type::Nullary(_) => todo!(), + Type::Prim(pr) => Ok(pr.into()), + Type::Tuple(members) => Ok(ast::Type::Tuple( + members + .into_iter() + .map(|ty| self.finalize_type(ty)) + .try_collect()?, + )), + Type::Fun { args, ret } => Ok(ast::Type::Function(ast::FunctionType { + args: args + .into_iter() + .map(|ty| self.finalize_type(ty)) + .try_collect()?, + ret: Box::new(self.finalize_type(*ret)?), + })), + }; + ret + } + + fn resolve_tv(&self, tv: TyVar) -> Result<Option<ast::Type<'static>>> { + let mut res = &Type::Exist(tv); + Ok(loop { + match res { + Type::Exist(tv) => { + res = match self.ctx.get(tv) { + Some(r) => r, + None => return Ok(None), + }; + } + Type::Univ(tv) => { + let ident = self.name_univ(*tv); + if let Some(r) = self.instantiations.resolve(&ident) { + res = r; + } else { + break Some(ast::Type::Var(ident)); + } + } + Type::Nullary(_) => todo!(), + Type::Prim(pr) => break Some((*pr).into()), + Type::Unit => break Some(ast::Type::Unit), + Type::Fun { args, ret } => todo!(), + Type::Tuple(_) => break Some(self.finalize_type(res.clone())?), + } + }) + } + + fn type_from_ast_type(&mut self, ast_type: ast::Type<'ast>) -> Type { + match ast_type { + ast::Type::Unit => Type::Unit, + ast::Type::Int => INT, + ast::Type::Float => FLOAT, + ast::Type::Bool => BOOL, + ast::Type::CString => CSTRING, + ast::Type::Tuple(members) => Type::Tuple( + members + .into_iter() + .map(|ty| self.type_from_ast_type(ty)) + .collect(), + ), + ast::Type::Function(ast::FunctionType { args, ret }) => Type::Fun { + args: args + .into_iter() + .map(|t| self.type_from_ast_type(t)) + .collect(), + ret: Box::new(self.type_from_ast_type(*ret)), + }, + ast::Type::Var(id) => Type::Univ({ + let opt_tv = { self.type_vars.borrow_mut().0.get_by_left(&id).copied() }; + opt_tv.unwrap_or_else(|| { + let tv = self.fresh_tv(); + self.type_vars + .borrow_mut() + .0 + .insert_no_overwrite(id, tv) + .unwrap(); + tv + }) + }), + } + } + + fn name_univ(&self, tv: TyVar) -> Ident<'static> { + let mut vars = self.type_vars.borrow_mut(); + vars.0 + .get_by_right(&tv) + .map(Ident::to_owned) + .unwrap_or_else(|| { + let name = loop { + let name = vars.1.make_name(); + if !vars.0.contains_left(&name) { + break name; + } + }; + vars.0.insert_no_overwrite(name.clone(), tv).unwrap(); + name + }) + } + + fn commit_instantiations(&mut self) -> HashMap<Ident<'ast>, Type> { + let mut res = HashMap::new(); + let mut ctx = mem::take(&mut self.ctx); + for (_, v) in ctx.iter_mut() { + if let Type::Univ(tv) = v { + let tv_name = self.name_univ(*tv); + if let Some(concrete) = self.instantiations.resolve(&tv_name) { + res.insert(tv_name, concrete.clone()); + *v = concrete.clone(); + } + } + } + self.ctx = ctx; + self.instantiations.pop(); + res + } + + fn types_match(&self, type_: &Type, ast_type: &ast::Type<'ast>) -> bool { + match (type_, ast_type) { + (Type::Univ(u), ast::Type::Var(v)) => { + Some(u) == self.type_vars.borrow().0.get_by_left(v) + } + (Type::Univ(_), _) => false, + (Type::Exist(_), _) => false, + (Type::Unit, ast::Type::Unit) => true, + (Type::Unit, _) => false, + (Type::Nullary(_), _) => todo!(), + (Type::Prim(pr), ty) => ast::Type::from(*pr) == *ty, + (Type::Tuple(members), ast::Type::Tuple(members2)) => members + .iter() + .zip(members2.iter()) + .all(|(t1, t2)| self.types_match(t1, t2)), + (Type::Tuple(members), _) => false, + (Type::Fun { args, ret }, ast::Type::Function(ft)) => { + args.len() == ft.args.len() + && args + .iter() + .zip(&ft.args) + .all(|(a1, a2)| self.types_match(a1, &a2)) + && self.types_match(&*ret, &*ft.ret) + } + (Type::Fun { .. }, _) => false, + } + } +} + +pub fn typecheck_expr(expr: ast::Expr) -> Result<hir::Expr<ast::Type>> { + let mut typechecker = Typechecker::new(); + let typechecked = typechecker.tc_expr(expr)?; + typechecker.finalize_expr(typechecked) +} + +pub fn typecheck_toplevel(decls: Vec<ast::Decl>) -> Result<Vec<hir::Decl<ast::Type>>> { + let mut typechecker = Typechecker::new(); + let mut res = Vec::with_capacity(decls.len()); + for decl in decls { + if let Some(hir_decl) = typechecker.tc_decl(decl)? { + let hir_decl = typechecker.finalize_decl(hir_decl)?; + res.push(hir_decl); + } + typechecker.ctx.clear(); + } + Ok(res) +} + +#[cfg(test)] +mod tests { + use super::*; + + macro_rules! assert_type { + ($expr: expr, $type: expr) => { + use crate::parser::{expr, type_}; + let parsed_expr = test_parse!(expr, $expr); + let parsed_type = test_parse!(type_, $type); + let res = typecheck_expr(parsed_expr).unwrap_or_else(|e| panic!("{}", e)); + assert!( + res.type_().alpha_equiv(&parsed_type), + "{} inferred type {}, but expected {}", + $expr, + res.type_(), + $type + ); + }; + + (toplevel($program: expr), $($decl: ident => $type: expr),+ $(,)?) => {{ + use crate::parser::{toplevel, type_}; + let program = test_parse!(toplevel, $program); + let res = typecheck_toplevel(program).unwrap_or_else(|e| panic!("{}", e)); + $( + let parsed_type = test_parse!(type_, $type); + let ident = Ident::try_from(::std::stringify!($decl)).unwrap(); + let decl = res.iter().find(|decl| { + matches!(decl, crate::ast::hir::Decl::Fun { name, .. } if name == &ident) + }).unwrap_or_else(|| panic!("Could not find declaration for {}", ident)); + assert!( + decl.type_().unwrap().alpha_equiv(&parsed_type), + "inferred type {} for {}, but expected {}", + decl.type_().unwrap(), + ident, + $type + ); + )+ + }}; + } + + macro_rules! assert_type_error { + ($expr: expr) => { + use crate::parser::expr; + let parsed_expr = test_parse!(expr, $expr); + let res = typecheck_expr(parsed_expr); + assert!( + res.is_err(), + "Expected type error, but got type: {}", + res.unwrap().type_() + ); + }; + } + + #[test] + fn literal_int() { + assert_type!("1", "int"); + } + + #[test] + fn conditional() { + assert_type!("if 1 == 2 then 3 else 4", "int"); + } + + #[test] + #[ignore] + fn add_bools() { + assert_type_error!("true + false"); + } + + #[test] + fn call_generic_function() { + assert_type!("(fn x = x) 1", "int"); + } + + #[test] + fn call_let_bound_generic() { + assert_type!("let id = fn x = x in id 1", "int"); + } + + #[test] + fn universal_ascripted_let() { + assert_type!("let id: fn a -> a = fn x = x in id 1", "int"); + } + + #[test] + fn call_generic_function_toplevel() { + assert_type!( + toplevel( + "ty id : fn a -> a + fn id x = x + + fn main = id 0" + ), + main => "fn -> int", + id => "fn a -> a", + ); + } + + #[test] + #[ignore] + fn let_generalization() { + assert_type!("let id = fn x = x in if id true then id 1 else 2", "int"); + } + + #[test] + fn concrete_function() { + assert_type!("fn x = x + 1", "fn int -> int"); + } + + #[test] + fn arg_ascriptions() { + assert_type!("fn (x: int) = x", "fn int -> int"); + } + + #[test] + fn call_concrete_function() { + assert_type!("(fn x = x + 1) 2", "int"); + } + + #[test] + fn conditional_non_bool() { + assert_type_error!("if 3 then true else false"); + } + + #[test] + fn let_int() { + assert_type!("let x = 1 in x", "int"); + } +} |